compiles & uploads

Merge branch 'atsamr' of github.com:adafruit/ArduinoCore-samd into atsamr
fix for USBcore
2018-09-09 19:21:47 -04:00 · 2018-09-09 19:18:47 -04:00 · 2018-09-09 19:13:00 -04:00 · 2018-09-09 19:13:00 -04:00 · 2018-09-09 19:12:26 -04:00 · 2018-09-09 19:12:26 -04:00
283 changed files with 1680 additions and 24411 deletions
--- a/.github/workflows/githubci.yml
+++ b/.github/workflows/githubci.yml
@ -1,63 +0,0 @@
-name: Build
-
-on: [pull_request, push]
-
-jobs:
-  build:
-    strategy:
-      fail-fast: false
-      matrix:
-        arduino-platform: ['metro_m0', 'hallowing', 'circuitplayground_m0',
-                           'metro_m4', 'pybadge_m4', 'pygamer_m4', 'hallowing_m4', 'pyportal_m4', 'pyportal_m4_titano']
-
-    runs-on: ubuntu-latest
-    
-    steps:
-    - name: Setup Python
-      uses: actions/setup-python@v1
-      with:
-        python-version: '3.x'
-        
-    - name: Checkout code
-      uses: actions/checkout@v2
-
-    - name: Checkout submodules
-      shell: bash
-      run: |
-        auth_header="$(git config --local --get http.https://github.com/.extraheader)"
-        git submodule sync --recursive
-        git -c "http.extraheader=$auth_header" -c protocol.version=2 submodule update --init --force --recursive      
-        
-    - name: Install Arduino CLI and Tools
-      run: |
-        # make all our directories we need for files and libraries
-        mkdir $HOME/.arduino15
-        mkdir $HOME/.arduino15/packages
-        mkdir $HOME/Arduino
-        mkdir $HOME/Arduino/libraries
-        curl -fsSL https://raw.githubusercontent.com/arduino/arduino-cli/master/install.sh | sh
-        echo "::add-path::$GITHUB_WORKSPACE/bin"
-        
-    - name: Install BSP and Libraries
-      env:
-        BSP_URL: https://adafruit.github.io/arduino-board-index/package_adafruit_index.json
-        BSP_PATH: .arduino15/packages/adafruit/hardware/samd
-        LIB_DEPS: FlashStorage SD
-      run: |
-        arduino-cli config init
-        arduino-cli core update-index
-        arduino-cli core update-index --additional-urls $BSP_URL        
-        arduino-cli core install arduino:samd --additional-urls $BSP_URL
-        arduino-cli core install adafruit:samd --additional-urls $BSP_URL
-        # Replace release BSP with our code
-        BSP_VERSION=`eval ls $HOME/$BSP_PATH`
-        rm -r $HOME/$BSP_PATH/*
-        ln -s $GITHUB_WORKSPACE $HOME/$BSP_PATH/$BSP_VERSION
-        arduino-cli lib install $LIB_DEPS
-
-    - name: Build examples
-      run: python3 extras/build_all.py ${{ matrix.arduino-platform }}
-
-    # How to mark this as allowed-to-fail?
-    - name: Build examples (-Wall)
-      run: python3 extras/build_all.py --all_warnings --warnings_do_not_cause_job_failure
--- a/.gitmodules
+++ b/.gitmodules
@ -1,3 +0,0 @@
-[submodule "cores/arduino/TinyUSB/Adafruit_TinyUSB_ArduinoCore"]
-	path = cores/arduino/TinyUSB/Adafruit_TinyUSB_ArduinoCore
-	url = https://github.com/adafruit/Adafruit_TinyUSB_ArduinoCore.git
--- a/35
+++ b/35
@ -1,40 +1,5 @@
 SAMD CORE ?.?.?? ????.??.??

-SAMD CORE 1.6.21 2019.04.01
-
-* MKR boards: changed I2C to sercom2, SPI1 + Serial2 to sercom4
-* Improved accuracy of delay() function. Thanks @BenF
-* MKR 1500: Changed SARA module to be powered off on boot
-
-SAMD CORE 1.6.20 2018.11.28
-
-* Replaced boolean type with bool in examples. Thanks @per1234
-* Added c++ linker command to allow to include libstdc++ when linking. Thanks @helmut64
-* CPX driver fixes. Thanks @dhalbert
-* I2S: Changed library to use 8 MHz oscillator source if 48MHz divider does not fit in 8 bits
-* UART: Added frame error handling
-* USB: Fixed memory leak on reconnects
-* SDU: Added support for Arduino M0. Thanks @jandrassy
-* Added arduinoOTA upload keys for Arduino M0. Thanks @jandrassy
-* USB: Fixed USB Host failures and fixed memory overwrite in USBHost. Thanks @gdsports
-* USB: Added method to return USB error code. Thanks @MarkFischer
-* CDC: Clear line state on end()
-* USB: Added USB device end() method
-* Removed requirement that the DAC is on A0. Thanks @GabrielNotman
-* Added alternate ports 44, 45 to make the SWCLK and SWDIO pins available on the Zero. Thanks @helmut64
-* Added defines for MKR pin layout
-* Fixed freeze in tone()
-* Added MKR NB 1500 variant and bootloader
-* Increased the default serial buffer size to 256
-
-SAMD CORE 1.6.19 2018.07.11
-
-* Fixed bootloader tools for .org boards
-* M0: Updated pin definitions for D6, D7 and D13 to match Zero
-* SPI: Fixed interrupt mask to block. Thanks @ggajoch
-* Added MKR WiFi 1010 variant and bootloader
-* Updated Windows Drivers to 1.4.0 and re-signed Adafruit_Circuit_Playground_Express.inf
-
 SAMD CORE 1.6.18 2018.03.05

 * Wire: Added support for general call (broadcast)
--- a/README.md
+++ b/README.md
@ -1,16 +1,47 @@
 # Arduino Core for SAMD21 and SAMD51 CPU

-[![Build Status](https://github.com/adafruit/ArduinoCore-samd/workflows/Build/badge.svg)](https://github.com/adafruit/ArduinoCore-samd/actions)
+## Known Issues:
+* gcc optimizations must be off for sketches to work consistently. We are working to track this down.
+* AREF must be tied to 3.3V for dac to work. This is a bug in the SAMD51 silicon.
+* USB host mode doesn't work yet
+* I2S doesn't work yet

 This repository contains the source code and configuration files of the Arduino Core
 for Atmel's SAMD21 and SAMD51 processor (used on the Arduino/Genuino Zero, MKR1000 and MKRZero boards).

 In particular, this adds support for the Adafruit SAMD Boards such as the Feather M0

-## Bugs or Issues
+## ATSAMD51 Installation on Arduino IDE

-* AREF must be tied to 3.3V for dac to work. This is a bug in the SAMD51 silicon.
-* USB host mode doesn't work yet
+The ATSAMD51 is a significantly new chip, so this is a detailed process for now! For the SAMD21, please install via the board manager (no extra steps required)
+
+1. Install Arduino IDE 1.8.5 or greater
+2. Install/update the Adafruit SAMD board support package if you have installed it
+3. Now we need to update CMSIS! Download https://github.com/adafruit/ArduinoModule-CMSIS-Atmel/archive/master.zip and unzip
+4. Find your Arduino CMSIS, in Mac its "~/Library/Arduino15/packages/arduino/tools/CMSIS-Atmel/1.1.0/CMSIS" version # may vary, you'll need "Go to folder..." feature in the Finder to get to " ~/Library/Arduino15" as it is hidden. In Windows it is "C:\Users\yourusername\AppData\Local\Arduino15\packages\arduino\tools\CMSIS-Atmel\1.1.0\CMSIS" Inside is a folder named Device
+
+For Linux: the Arduino stuff is located in ~/.arduino15/packages/arduino/tools/CMSIS-Atmel/1.1.0/CMSIS
+
+5. Inside the downloaded CMSIS zip, go into the CMSIS-Atmel/CMSIS folder, you should see a folder named Device. *DRAG THE DEVICE FOLDER ONLY* from the zip to your arduino Library folder so that Device is merged with Device. It will replace a bunch of files.
+
+For Linux, it may be better to just delete the original Device Folder then copy over the new one - the drag/drop worked ok on MACOS, but not so well on my Linux box.  
+
+6. You will also need to replace bossac. For Windows or Mac: Go here https://github.com/adafruit/BOSSA/releases and download either windows exe or mac app of latest bossac. unzip.  Go to Step 12.
+
+For Linux users it is best to build a copy of bossac locally - 
+clone the Adafruit Repostitory to somewhere on your local machine.
+```
+git clone https://github.com/adafruit/BOSSA.git
+change to the arduino branch
+git checkout arduino
+```
+Follow the instructions to build bossac in README.md or at https://github.com/adafruit/BOSSA/tree/arduino.
+
+7. Replace the binary at ".../Library/Arduino15/packages/arduino/tools/bossac/1.7.0/bossac" or "...\AppData\Local\Arduino15\packages\arduino\tools\bossac\1.7.0\bossac"
+8. On Windows 7 you will also need to install the updated serial driver, download https://github.com/adafruit/Adafruit_Windows_Drivers/archive/master.zip to get all the drivers, and point the Device Manager to the unzipped folder. It isn't signed, so just approve the installation manually.
+13. That's it!
+
+## Bugs or Issues

 If you find a bug you can submit an issue here on github:

--- a/boards.txt
+++ b/boards.txt
--- a/bootloaders/blmbadge/bootloader-blm_badge.bin
+++ b/bootloaders/blmbadge/bootloader-blm_badge.bin
--- a/bootloaders/grand_central_m4/bootloader-grandcentral_m4.bin
+++ b/bootloaders/grand_central_m4/bootloader-grandcentral_m4.bin
--- a/bootloaders/matrixportalM4/bootloader-matrixportal_m4.bin
+++ b/bootloaders/matrixportalM4/bootloader-matrixportal_m4.bin
--- a/bootloaders/mkrnb1500/samd21_sam_ba_arduino_mkrnb1500.bin
+++ b/bootloaders/mkrnb1500/samd21_sam_ba_arduino_mkrnb1500.bin
--- a/bootloaders/mkrnb1500/samd21_sam_ba_arduino_mkrnb1500.hex
+++ b/bootloaders/mkrnb1500/samd21_sam_ba_arduino_mkrnb1500.hex
@ -1,502 +0,0 @@
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--- a/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21e15a.h
+++ b/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21e15a.h
@ -218,11 +218,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21e16a.h
+++ b/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21e16a.h
@ -218,11 +218,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21e17a.h
+++ b/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21e17a.h
@ -218,11 +218,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21e18a.h
+++ b/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21e18a.h
@ -218,11 +218,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21g15a.h
+++ b/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21g15a.h
@ -222,11 +222,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21g16a.h
+++ b/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21g16a.h
@ -222,11 +222,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21g17a.h
+++ b/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21g17a.h
@ -222,11 +222,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21g18a.h
+++ b/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21g18a.h
@ -222,11 +222,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21j15a.h
+++ b/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21j15a.h
@ -226,11 +226,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21j16a.h
+++ b/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21j16a.h
@ -226,11 +226,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21j17a.h
+++ b/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21j17a.h
@ -226,11 +226,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21j18a.h
+++ b/bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21j18a.h
@ -226,11 +226,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/qtpyM0/bootloader-qtpy_m0.bin
+++ b/bootloaders/qtpyM0/bootloader-qtpy_m0.bin
--- a/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21e15a.h
+++ b/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21e15a.h
@ -218,11 +218,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21e16a.h
+++ b/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21e16a.h
@ -218,11 +218,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21e17a.h
+++ b/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21e17a.h
@ -218,11 +218,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21e18a.h
+++ b/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21e18a.h
@ -218,11 +218,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21g15a.h
+++ b/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21g15a.h
@ -222,11 +222,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21g16a.h
+++ b/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21g16a.h
@ -222,11 +222,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21g17a.h
+++ b/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21g17a.h
@ -222,11 +222,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21g18a.h
+++ b/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21g18a.h
@ -222,11 +222,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21j15a.h
+++ b/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21j15a.h
@ -226,11 +226,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21j16a.h
+++ b/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21j16a.h
@ -226,11 +226,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21j17a.h
+++ b/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21j17a.h
@ -226,11 +226,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21j18a.h
+++ b/bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21j18a.h
@ -226,11 +226,7 @@ void I2S_Handler                 ( void );
 * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
 */

-#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
-  #error "Little Endian is already defined, but to different value than expected?!"
-#else
-  #define LITTLE_ENDIAN          1
-#endif
+#define LITTLE_ENDIAN          1        
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */
--- a/bootloaders/zero/board_definitions.h
+++ b/bootloaders/zero/board_definitions.h
@ -20,35 +20,6 @@
 #ifndef _BOARD_DEFINITIONS_H_
 #define _BOARD_DEFINITIONS_H_

-#if defined(BOARD_ID_arduino_zero)
-  #include "board_definitions_arduino_zero.h"
-#elif defined(BOARD_ID_genuino_zero)
-  #include "board_definitions_genuino_zero.h"
-#elif defined(BOARD_ID_arduino_mkr1000)
-  #include "board_definitions_arduino_mkr1000.h"
-#elif defined(BOARD_ID_genuino_mkr1000)
-  #include "board_definitions_genuino_mkr1000.h"
-#elif defined(BOARD_ID_arduino_mkrzero)
-  #include "board_definitions_arduino_mkrzero.h"
-#elif defined(BOARD_ID_arduino_mkrfox1200)
-  #include "board_definitions_arduino_mkrfox1200.h"
-#elif defined(BOARD_ID_arduino_mkrgsm1400)
-  #include "board_definitions_arduino_mkrgsm1400.h"
-#elif defined(BOARD_ID_arduino_mkrwan1300)
-  #include "board_definitions_arduino_mkrwan1300.h"
-#elif defined(BOARD_ID_arduino_mkrwifi1010)
-  #include "board_definitions_arduino_mkrwifi1010.h"
-#elif defined(BOARD_ID_arduino_mkrnb1500)
-  #include "board_definitions_arduino_mkrnb1500.h"
-#else
-  #error You must define a BOARD_ID and add the corresponding definitions in board_definitions.h
-#endif
-
-// Common definitions
-// ------------------
-
-#define BOOT_PIN_MASK (1U << (BOOT_LOAD_PIN & 0x1f))
-
 /*
 * If BOOT_DOUBLE_TAP_ADDRESS is defined the bootloader is started by
 * quickly tapping two times on the reset button.
--- a/bootloaders/zero/board_definitions_arduino_mkrnb1500.h
+++ b/bootloaders/zero/board_definitions_arduino_mkrnb1500.h
@ -1,86 +0,0 @@
-/*
-  Copyright (c) 2016 Arduino LLC.  All right reserved.
-
-  This library is free software; you can redistribute it and/or
-  modify it under the terms of the GNU Lesser General Public
-  License as published by the Free Software Foundation; either
-  version 2.1 of the License, or (at your option) any later version.
-
-  This library is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
-  See the GNU Lesser General Public License for more details.
-
-  You should have received a copy of the GNU Lesser General Public
-  License along with this library; if not, write to the Free Software
-  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
-*/
-
-#ifndef _BOARD_DEFINITIONS_H_
-#define _BOARD_DEFINITIONS_H_
-
-/*
- * USB device definitions
- */
-#define STRING_PRODUCT "Arduino MKR NB 1500"
-#define USB_VID_HIGH   0x23
-#define USB_VID_LOW    0x41
-#define USB_PID_HIGH   0x00
-#define USB_PID_LOW    0x55
-
-/*
- * If BOOT_DOUBLE_TAP_ADDRESS is defined the bootloader is started by
- * quickly tapping two times on the reset button.
- * BOOT_DOUBLE_TAP_ADDRESS must point to a free SRAM cell that must not
- * be touched from the loaded application.
- */
-#define BOOT_DOUBLE_TAP_ADDRESS           (0x20007FFCul)
-#define BOOT_DOUBLE_TAP_DATA              (*((volatile uint32_t *) BOOT_DOUBLE_TAP_ADDRESS))
-
-/*
- * If BOOT_LOAD_PIN is defined the bootloader is started if the selected
- * pin is tied LOW.
- */
-//#define BOOT_LOAD_PIN                     PIN_PA21
-//#define BOOT_LOAD_PIN                     PIN_PA15
-
-#define BOOT_USART_MODULE                 SERCOM5
-#define BOOT_USART_BUS_CLOCK_INDEX        PM_APBCMASK_SERCOM5
-#define BOOT_USART_PER_CLOCK_INDEX        GCLK_CLKCTRL_ID_SERCOM5_CORE_Val
-#define BOOT_USART_PAD_SETTINGS           UART_RX_PAD3_TX_PAD2
-#define BOOT_USART_PAD3                   PINMUX_PB23D_SERCOM5_PAD3
-#define BOOT_USART_PAD2                   PINMUX_PB22D_SERCOM5_PAD2
-#define BOOT_USART_PAD1                   PINMUX_UNUSED
-#define BOOT_USART_PAD0                   PINMUX_UNUSED
-
-/* Master clock frequency */
-#define CPU_FREQUENCY                     (48000000ul)
-#define VARIANT_MCK                       CPU_FREQUENCY
-
-/* Frequency of the board main oscillator */
-#define VARIANT_MAINOSC                   (32768ul)
-
-/* Calibration values for DFLL48 pll */
-#define NVM_SW_CALIB_DFLL48M_COARSE_VAL   (58)
-#define NVM_SW_CALIB_DFLL48M_FINE_VAL     (64)
-
-/*
- * LEDs definitions
- */
-// PA20 (digital pin 6)
-#define BOARD_LED_PORT                    (0)
-#define BOARD_LED_PIN                     (20)
-
-#define CONFIGURE_PMIC                    1
-#define PMIC_PIN_SCL                      12
-#define PMIC_PIN_SDA                      11
-#define PMIC_SERCOM                       SERCOM0                      
-
-// No RX/TX led
-//#define BOARD_LEDRX_PORT
-//#define BOARD_LEDRX_PIN
-
-//#define BOARD_LEDTX_PORT
-//#define BOARD_LEDTX_PIN
-
-#endif // _BOARD_DEFINITIONS_H_
--- a/bootloaders/zero/build_all_bootloaders.sh
+++ b/bootloaders/zero/build_all_bootloaders.sh
@ -25,8 +25,5 @@ mv -v samd21_sam_ba_arduino_mkrwan1300.* ../mkrwan1300/
 BOARD_ID=arduino_mkrwifi1010 NAME=samd21_sam_ba_arduino_mkrwifi1010 make clean all
 mv -v samd21_sam_ba_arduino_mkrwifi1010.* ../mkrwifi1010/

-BOARD_ID=arduino_mkrnb1500 NAME=samd21_sam_ba_arduino_mkrnb1500 make clean all
-mv -v samd21_sam_ba_arduino_mkrnb1500.* ../mkrnb1500/
-
 echo Done building bootloaders!

--- a/cores/arduino/Arduino.h
+++ b/cores/arduino/Arduino.h
@ -97,33 +97,8 @@ void loop( void ) ;
 #undef abs
 #endif // abs

-#ifdef __cplusplus
-  template<class T, class L> 
-  auto min(const T& a, const L& b) -> decltype((b < a) ? b : a)
-  {
-    return (b < a) ? b : a;
-  }
-
-  template<class T, class L> 
-  auto max(const T& a, const L& b) -> decltype((b < a) ? b : a)
-  {
-    return (a < b) ? b : a;
-  }
-#else
-#ifndef min
-#define min(a,b) \
-   ({ __typeof__ (a) _a = (a); \
-       __typeof__ (b) _b = (b); \
-     _a < _b ? _a : _b; })
-#endif
-#ifndef max
-#define max(a,b) \
-   ({ __typeof__ (a) _a = (a); \
-       __typeof__ (b) _b = (b); \
-     _a > _b ? _a : _b; })
-#endif
-#endif
-
+#define min(a,b) ((a)<(b)?(a):(b))
+#define max(a,b) ((a)>(b)?(a):(b))
 #define abs(x) ((x)>0?(x):-(x))
 #define constrain(amt,low,high) ((amt)<(low)?(low):((amt)>(high)?(high):(amt)))
 #define round(x)     ((x)>=0?(long)((x)+0.5):(long)((x)-0.5))
@ -149,14 +124,10 @@ void loop( void ) ;
 #define digitalPinToInterrupt(P)   ( P )
 #endif

-// USB
-#ifdef USE_TINYUSB
-#include "Adafruit_TinyUSB_Core.h"
-#else
+// USB Device
 #include "USB/USBDesc.h"
 #include "USB/USBCore.h"
 #include "USB/USBAPI.h"
 #include "USB/USB_host.h"
-#endif

 #endif // Arduino_h
--- a/cores/arduino/HardwareSerial.h
+++ b/cores/arduino/HardwareSerial.h
@ -68,7 +68,7 @@ class HardwareSerial : public Stream
 {
  public:
    virtual void begin(unsigned long) {}
-    virtual void begin(unsigned long, uint16_t) {}
+    virtual void begin(unsigned long baudrate, uint16_t config) {}
    virtual void end() {}
    virtual int available(void) = 0;
    virtual int peek(void) = 0;
--- a/cores/arduino/Print.cpp
+++ b/cores/arduino/Print.cpp
@ -186,16 +186,6 @@ size_t Print::println(const Printable& x)
  return n;
 }

-void Print::printf(const char format[], ...)
-{
-  char buf[PRINTF_BUF];
-  va_list ap;
-  va_start(ap, format);
-  vsnprintf(buf, sizeof(buf), format, ap);
-  write(buf);
-  va_end(ap);
-}
-
 // Private Methods /////////////////////////////////////////////////////////////

 size_t Print::printNumber(unsigned long n, uint8_t base)
@ -248,14 +238,14 @@ size_t Print::printFloat(double number, uint8_t digits)

  // Print the decimal point, but only if there are digits beyond
  if (digits > 0) {
-    n += print(".");
+    n += print('.');
  }

  // Extract digits from the remainder one at a time
  while (digits-- > 0)
  {
    remainder *= 10.0;
-    unsigned int toPrint = (unsigned int)remainder;
+    unsigned int toPrint = (unsigned int)(remainder);
    n += print(toPrint);
    remainder -= toPrint;
  }
--- a/cores/arduino/Print.h
+++ b/cores/arduino/Print.h
@ -21,8 +21,6 @@

 #include <inttypes.h>
 #include <stdio.h> // for size_t
-#include <stdarg.h> // for printf
-#define PRINTF_BUF 80

 #include "WString.h"
 #include "Printable.h"
@ -30,6 +28,9 @@
 #define DEC 10
 #define HEX 16
 #define OCT 8
+#ifdef BIN // Prevent warnings if BIN is previously defined in "iotnx4.h" or similar
+#undef BIN
+#endif
 #define BIN 2

 class Print
@ -84,8 +85,6 @@ class Print
    size_t println(double, int = 2);
    size_t println(const Printable&);
    size_t println(void);
-    
-    void printf(const char[], ...);

    virtual void flush() { /* Empty implementation for backward compatibility */ }
 };
--- a/cores/arduino/RingBuffer.h
+++ b/cores/arduino/RingBuffer.h
@ -27,10 +27,7 @@
 // using a ring buffer (I think), in which head is the index of the location
 // to which to write the next incoming character and tail is the index of the
 // location from which to read.
-
-#ifndef SERIAL_BUFFER_SIZE
-#define SERIAL_BUFFER_SIZE 350
-#endif
+#define SERIAL_BUFFER_SIZE 164

 template <int N>
 class RingBufferN
--- a/cores/arduino/SERCOM.cpp
+++ b/cores/arduino/SERCOM.cpp
@ -30,29 +30,11 @@
 SERCOM::SERCOM(Sercom* s)
 {
  sercom = s;
-
-#if defined(__SAMD51__)
-  // A briefly-available but now deprecated feature had the SPI clock source
-  // set via a compile-time setting (MAX_SPI)...problem was this affected
-  // ALL SERCOMs, whereas some (anything read/write, e.g. SD cards) should
-  // not exceed the standard 24 MHz setting.  Newer code, if it needs faster
-  // write-only SPI (e.g. to screen), should override the SERCOM clock on a
-  // per-peripheral basis.  Nonetheless, we check SERCOM_SPI_FREQ_REF here
-  // (MAX_SPI * 2) to retain compatibility with any interim projects that
-  // might have relied on the compile-time setting.  But please, don't.
- #if SERCOM_SPI_FREQ_REF == F_CPU       // F_CPU clock = GCLK0
-  clockSource = SERCOM_CLOCK_SOURCE_FCPU;
- #elif SERCOM_SPI_FREQ_REF == 48000000  // 48 MHz clock = GCLK1 (standard)
-  clockSource = SERCOM_CLOCK_SOURCE_48M;
- #elif SERCOM_SPI_FREQ_REF == 100000000 // 100 MHz clock = GCLK2
-  clockSource = SERCOM_CLOCK_SOURCE_100M;
- #endif
-#endif // end __SAMD51__
 }

-/* =========================
- * ===== Sercom UART
- * =========================
+/* 	=========================
+ *	===== Sercom UART
+ *	=========================
 */
 void SERCOM::initUART(SercomUartMode mode, SercomUartSampleRate sampleRate, uint32_t baudrate)
 {
@ -60,12 +42,12 @@ void SERCOM::initUART(SercomUartMode mode, SercomUartSampleRate sampleRate, uint
  resetUART();

  //Setting the CTRLA register
-  sercom->USART.CTRLA.reg = SERCOM_USART_CTRLA_MODE(mode) |
-                            SERCOM_USART_CTRLA_SAMPR(sampleRate);
+  sercom->USART.CTRLA.reg =	SERCOM_USART_CTRLA_MODE(mode) |
+                SERCOM_USART_CTRLA_SAMPR(sampleRate);

  //Setting the Interrupt register
-  sercom->USART.INTENSET.reg = SERCOM_USART_INTENSET_RXC |  //Received complete
-                               SERCOM_USART_INTENSET_ERROR; //All others errors
+  sercom->USART.INTENSET.reg =	SERCOM_USART_INTENSET_RXC |  //Received complete
+                                SERCOM_USART_INTENSET_ERROR; //All others errors

  if ( mode == UART_INT_CLOCK )
  {
@ -93,22 +75,20 @@ void SERCOM::initUART(SercomUartMode mode, SercomUartSampleRate sampleRate, uint
 void SERCOM::initFrame(SercomUartCharSize charSize, SercomDataOrder dataOrder, SercomParityMode parityMode, SercomNumberStopBit nbStopBits)
 {
  //Setting the CTRLA register
-  sercom->USART.CTRLA.reg |=
-    SERCOM_USART_CTRLA_FORM((parityMode == SERCOM_NO_PARITY ? 0 : 1) ) |
-    dataOrder << SERCOM_USART_CTRLA_DORD_Pos;
+  sercom->USART.CTRLA.reg |=	SERCOM_USART_CTRLA_FORM( (parityMode == SERCOM_NO_PARITY ? 0 : 1) ) |
+                dataOrder << SERCOM_USART_CTRLA_DORD_Pos;

  //Setting the CTRLB register
-  sercom->USART.CTRLB.reg |= SERCOM_USART_CTRLB_CHSIZE(charSize) |
-    nbStopBits << SERCOM_USART_CTRLB_SBMODE_Pos |
-    (parityMode == SERCOM_NO_PARITY ? 0 : parityMode) <<
-      SERCOM_USART_CTRLB_PMODE_Pos; //If no parity use default value
+  sercom->USART.CTRLB.reg |=	SERCOM_USART_CTRLB_CHSIZE(charSize) |
+                nbStopBits << SERCOM_USART_CTRLB_SBMODE_Pos |
+                (parityMode == SERCOM_NO_PARITY ? 0 : parityMode) << SERCOM_USART_CTRLB_PMODE_Pos; //If no parity use default value
 }

 void SERCOM::initPads(SercomUartTXPad txPad, SercomRXPad rxPad)
 {
  //Setting the CTRLA register
-  sercom->USART.CTRLA.reg |= SERCOM_USART_CTRLA_TXPO(txPad) |
-                             SERCOM_USART_CTRLA_RXPO(rxPad);
+  sercom->USART.CTRLA.reg |=	SERCOM_USART_CTRLA_TXPO(txPad) |
+                SERCOM_USART_CTRLA_RXPO(rxPad);

  // Enable Transceiver and Receiver
  sercom->USART.CTRLB.reg |= SERCOM_USART_CTRLB_TXEN | SERCOM_USART_CTRLB_RXEN ;
@ -221,9 +201,9 @@ void SERCOM::disableDataRegisterEmptyInterruptUART()
  sercom->USART.INTENCLR.reg = SERCOM_USART_INTENCLR_DRE;
 }

-/* =========================
- * ===== Sercom SPI
- * =========================
+/*	=========================
+ *	===== Sercom SPI
+ *	=========================
 */
 void SERCOM::initSPI(SercomSpiTXPad mosi, SercomRXPad miso, SercomSpiCharSize charSize, SercomDataOrder dataOrder)
 {
@ -231,13 +211,13 @@ void SERCOM::initSPI(SercomSpiTXPad mosi, SercomRXPad miso, SercomSpiCharSize ch
  initClockNVIC();

 #if defined(__SAMD51__)
-  sercom->SPI.CTRLA.reg = SERCOM_SPI_CTRLA_MODE(0x3)  |  // master mode
-                          SERCOM_SPI_CTRLA_DOPO(mosi) |
-                          SERCOM_SPI_CTRLA_DIPO(miso) |
-                          dataOrder << SERCOM_SPI_CTRLA_DORD_Pos;
+	sercom->SPI.CTRLA.reg =	SERCOM_SPI_CTRLA_MODE(0x3) |  //master mode
+						SERCOM_SPI_CTRLA_DOPO(mosi) |
+						SERCOM_SPI_CTRLA_DIPO(miso) |
+						dataOrder << SERCOM_SPI_CTRLA_DORD_Pos;
 #else
  //Setting the CTRLA register
-  sercom->SPI.CTRLA.reg = SERCOM_SPI_CTRLA_MODE_SPI_MASTER |
+  sercom->SPI.CTRLA.reg =	SERCOM_SPI_CTRLA_MODE_SPI_MASTER |
                          SERCOM_SPI_CTRLA_DOPO(mosi) |
                          SERCOM_SPI_CTRLA_DIPO(miso) |
                          dataOrder << SERCOM_SPI_CTRLA_DORD_Pos;
@ -245,9 +225,10 @@ void SERCOM::initSPI(SercomSpiTXPad mosi, SercomRXPad miso, SercomSpiCharSize ch

  //Setting the CTRLB register
  sercom->SPI.CTRLB.reg = SERCOM_SPI_CTRLB_CHSIZE(charSize) |
-                          SERCOM_SPI_CTRLB_RXEN; //Active the SPI receiver.
+                          SERCOM_SPI_CTRLB_RXEN;	//Active the SPI receiver.

  while( sercom->SPI.SYNCBUSY.bit.CTRLB == 1 );
+  
 }

 void SERCOM::initSPIClock(SercomSpiClockMode clockMode, uint32_t baudrate)
@ -266,8 +247,8 @@ void SERCOM::initSPIClock(SercomSpiClockMode clockMode, uint32_t baudrate)
    cpol = 1;

  //Setting the CTRLA register
-  sercom->SPI.CTRLA.reg |= ( cpha << SERCOM_SPI_CTRLA_CPHA_Pos ) |
-                           ( cpol << SERCOM_SPI_CTRLA_CPOL_Pos );
+  sercom->SPI.CTRLA.reg |=	( cpha << SERCOM_SPI_CTRLA_CPHA_Pos ) |
+                            ( cpol << SERCOM_SPI_CTRLA_CPOL_Pos );

  //Synchronous arithmetic
  sercom->SPI.BAUD.reg = calculateBaudrateSynchronous(baudrate);
@ -321,13 +302,14 @@ SercomDataOrder SERCOM::getDataOrderSPI()

 void SERCOM::setBaudrateSPI(uint8_t divider)
 {
-  disableSPI(); // Register is enable-protected
+  //Can't divide by 0
+  if(divider == 0)
+    return;

-#if defined(__SAMD51__)
-  sercom->SPI.BAUD.reg = calculateBaudrateSynchronous(freqRef / divider);
-#else
-  sercom->SPI.BAUD.reg = calculateBaudrateSynchronous(SERCOM_SPI_FREQ_REF / divider);
-#endif
+  //Register enable-protected
+  disableSPI();
+
+  sercom->SPI.BAUD.reg = calculateBaudrateSynchronous( SERCOM_FREQ_REF / divider );

  enableSPI();
 }
@ -358,7 +340,10 @@ uint8_t SERCOM::transferDataSPI(uint8_t data)
 {
  sercom->SPI.DATA.bit.DATA = data; // Writing data into Data register

-  while(sercom->SPI.INTFLAG.bit.RXC == 0); // Waiting Complete Reception
+  while( sercom->SPI.INTFLAG.bit.RXC == 0 )
+  {
+    // Waiting Complete Reception
+  }

  return sercom->SPI.DATA.bit.DATA;  // Reading data
 }
@ -376,30 +361,25 @@ bool SERCOM::isDataRegisterEmptySPI()

 //bool SERCOM::isTransmitCompleteSPI()
 //{
-//  //TXC : Transmit complete
-//  return sercom->SPI.INTFLAG.bit.TXC;
+//	//TXC : Transmit complete
+//	return sercom->SPI.INTFLAG.bit.TXC;
 //}
 //
 //bool SERCOM::isReceiveCompleteSPI()
 //{
-//  //RXC : Receive complete
-//  return sercom->SPI.INTFLAG.bit.RXC;
+//	//RXC : Receive complete
+//	return sercom->SPI.INTFLAG.bit.RXC;
 //}

-uint8_t SERCOM::calculateBaudrateSynchronous(uint32_t baudrate) {
-#if defined(__SAMD51__)
-  uint16_t b = freqRef / (2 * baudrate);
-#else
-  uint16_t b = SERCOM_SPI_FREQ_REF / (2 * baudrate);
-#endif
-  if(b > 0) b--; // Don't -1 on baud calc if already at 0
-  return b;
+uint8_t SERCOM::calculateBaudrateSynchronous(uint32_t baudrate)
+{
+  return SERCOM_FREQ_REF / (2 * baudrate) - 1;
 }


-/* =========================
- * ===== Sercom WIRE
- * =========================
+/*	=========================
+ *	===== Sercom WIRE
+ *	=========================
 */
 void SERCOM::resetWIRE()
 {
@ -537,18 +517,8 @@ bool SERCOM::startTransmissionWIRE(uint8_t address, SercomWireReadWriteFlag flag
  // 7-bits address + 1-bits R/W
  address = (address << 0x1ul) | flag;

-  // If another master owns the bus or the last bus owner has not properly
-  // sent a stop, return failure early. This will prevent some misbehaved
-  // devices from deadlocking here at the cost of the caller being responsible
-  // for retrying the failed transmission. See SercomWireBusState for the
-  // possible bus states.
-  if(!isBusOwnerWIRE())
-  {
-    if( isBusBusyWIRE() || (isArbLostWIRE() && !isBusIdleWIRE()) || isBusUnknownWIRE() )
-    {
-      return false;
-    }
-  }
+  // Wait idle or owner bus mode
+   while ( !isBusIdleWIRE() && !isBusOwnerWIRE() );

  // Send start and address
  sercom->I2CM.ADDR.bit.ADDR = address;
@ -644,21 +614,6 @@ bool SERCOM::isBusOwnerWIRE( void )
  return sercom->I2CM.STATUS.bit.BUSSTATE == WIRE_OWNER_STATE;
 }

-bool SERCOM::isBusUnknownWIRE( void )
-{
-  return sercom->I2CM.STATUS.bit.BUSSTATE == WIRE_UNKNOWN_STATE;
-}
-
-bool SERCOM::isArbLostWIRE( void )
-{
-  return sercom->I2CM.STATUS.bit.ARBLOST == 1;
-}
-
-bool SERCOM::isBusBusyWIRE( void )
-{
-  return sercom->I2CM.STATUS.bit.BUSSTATE == WIRE_BUSY_STATE;
-}
-
 bool SERCOM::isDataReadyWIRE( void )
 {
  return sercom->I2CS.INTFLAG.bit.DRDY;
@ -714,152 +669,199 @@ uint8_t SERCOM::readDataWIRE( void )
  }
 }

-#if defined(__SAMD51__)
-
-static const struct {
-  Sercom   *sercomPtr;
-  uint8_t   id_core;
-  uint8_t   id_slow;
-  IRQn_Type irq[4];
-} sercomData[] = {
-  { SERCOM0, SERCOM0_GCLK_ID_CORE, SERCOM0_GCLK_ID_SLOW,
-    SERCOM0_0_IRQn, SERCOM0_1_IRQn, SERCOM0_2_IRQn, SERCOM0_3_IRQn },
-  { SERCOM1, SERCOM1_GCLK_ID_CORE, SERCOM1_GCLK_ID_SLOW,
-    SERCOM1_0_IRQn, SERCOM1_1_IRQn, SERCOM1_2_IRQn, SERCOM1_3_IRQn },
-  { SERCOM2, SERCOM2_GCLK_ID_CORE, SERCOM2_GCLK_ID_SLOW,
-    SERCOM2_0_IRQn, SERCOM2_1_IRQn, SERCOM2_2_IRQn, SERCOM2_3_IRQn },
-  { SERCOM3, SERCOM3_GCLK_ID_CORE, SERCOM3_GCLK_ID_SLOW,
-    SERCOM3_0_IRQn, SERCOM3_1_IRQn, SERCOM3_2_IRQn, SERCOM3_3_IRQn },
-  { SERCOM4, SERCOM4_GCLK_ID_CORE, SERCOM4_GCLK_ID_SLOW,
-    SERCOM4_0_IRQn, SERCOM4_1_IRQn, SERCOM4_2_IRQn, SERCOM4_3_IRQn },
-  { SERCOM5, SERCOM5_GCLK_ID_CORE, SERCOM5_GCLK_ID_SLOW,
-    SERCOM5_0_IRQn, SERCOM5_1_IRQn, SERCOM5_2_IRQn, SERCOM5_3_IRQn },
-#if defined(SERCOM6)
-  { SERCOM6, SERCOM6_GCLK_ID_CORE, SERCOM6_GCLK_ID_SLOW,
-    SERCOM6_0_IRQn, SERCOM6_1_IRQn, SERCOM6_2_IRQn, SERCOM6_3_IRQn },
-#endif
-#if defined(SERCOM7)
-  { SERCOM7, SERCOM7_GCLK_ID_CORE, SERCOM7_GCLK_ID_SLOW,
-    SERCOM7_0_IRQn, SERCOM7_1_IRQn, SERCOM7_2_IRQn, SERCOM7_3_IRQn },
-#endif
-};
-
-#else // end if SAMD51 (prob SAMD21)
-
-static const struct {
-  Sercom   *sercomPtr;
-  uint8_t   clock;
-  IRQn_Type irqn;
-} sercomData[] = {
-  SERCOM0, GCM_SERCOM0_CORE, SERCOM0_IRQn,
-  SERCOM1, GCM_SERCOM1_CORE, SERCOM1_IRQn,
-  SERCOM2, GCM_SERCOM2_CORE, SERCOM2_IRQn,
-  SERCOM3, GCM_SERCOM3_CORE, SERCOM3_IRQn,
-#if defined(SERCOM4)
-  SERCOM4, GCM_SERCOM4_CORE, SERCOM4_IRQn,
-#endif
-#if defined(SERCOM5)
-  SERCOM5, GCM_SERCOM5_CORE, SERCOM5_IRQn,
-#endif
-};
-
-#endif // end !SAMD51
-
-int8_t SERCOM::getSercomIndex(void) {
-  for(uint8_t i=0; i<(sizeof(sercomData) / sizeof(sercomData[0])); i++) {
-    if(sercom == sercomData[i].sercomPtr) return i;
-  }
-  return -1;
-}
-
-#if defined(__SAMD51__)
-// This is currently for overriding an SPI SERCOM's clock source only --
-// NOT for UART or WIRE SERCOMs, where it will have unintended consequences.
-// It does not check.
-// SERCOM clock source override is available only on SAMD51 (not 21).
-// A dummy function for SAMD21 (compiles to nothing) is present in SERCOM.h
-// so user code doesn't require a lot of conditional situations.
-void SERCOM::setClockSource(int8_t idx, SercomClockSource src, bool core) {
-
-  if(src == SERCOM_CLOCK_SOURCE_NO_CHANGE) return;
-
-  uint8_t clk_id = core ? sercomData[idx].id_core : sercomData[idx].id_slow;
-
-  GCLK->PCHCTRL[clk_id].bit.CHEN = 0;     // Disable timer
-  while(GCLK->PCHCTRL[clk_id].bit.CHEN);  // Wait for disable
-
-  if(core) clockSource = src; // Save SercomClockSource value
-
-  // From cores/arduino/startup.c:
-  // GCLK0 = F_CPU
-  // GCLK1 = 48 MHz
-  // GCLK2 = 100 MHz
-  // GCLK3 = XOSC32K
-  // GCLK4 = 12 MHz
-  if(src == SERCOM_CLOCK_SOURCE_FCPU) {
-    GCLK->PCHCTRL[clk_id].reg =
-      GCLK_PCHCTRL_GEN_GCLK0_Val | (1 << GCLK_PCHCTRL_CHEN_Pos);
-    if(core) freqRef = F_CPU; // Save clock frequency value
-  } else if(src == SERCOM_CLOCK_SOURCE_48M) {
-    GCLK->PCHCTRL[clk_id].reg =
-      GCLK_PCHCTRL_GEN_GCLK1_Val | (1 << GCLK_PCHCTRL_CHEN_Pos);
-    if(core) freqRef = 48000000;
-  } else if(src == SERCOM_CLOCK_SOURCE_100M) {
-    GCLK->PCHCTRL[clk_id].reg =
-      GCLK_PCHCTRL_GEN_GCLK2_Val | (1 << GCLK_PCHCTRL_CHEN_Pos);
-    if(core) freqRef = 100000000;
-  } else if(src == SERCOM_CLOCK_SOURCE_32K) {
-    GCLK->PCHCTRL[clk_id].reg =
-      GCLK_PCHCTRL_GEN_GCLK3_Val | (1 << GCLK_PCHCTRL_CHEN_Pos);
-    if(core) freqRef = 32768;
-  } else if(src == SERCOM_CLOCK_SOURCE_12M) {
-    GCLK->PCHCTRL[clk_id].reg =
-      GCLK_PCHCTRL_GEN_GCLK4_Val | (1 << GCLK_PCHCTRL_CHEN_Pos);
-    if(core) freqRef = 12000000;
-  }
-
-  while(!GCLK->PCHCTRL[clk_id].bit.CHEN); // Wait for clock enable
-}
-#endif

 void SERCOM::initClockNVIC( void )
 {
-  int8_t idx = getSercomIndex();
-  if(idx < 0) return; // We got a problem here

 #if defined(__SAMD51__)
+	uint32_t clk_core;
+	uint32_t clk_slow;
+	
+	if(sercom == SERCOM0)
+	{
+		clk_core = SERCOM0_GCLK_ID_CORE;
+		clk_slow = SERCOM0_GCLK_ID_SLOW;

-  for(uint8_t i=0; i<4; i++) {
-    NVIC_ClearPendingIRQ(sercomData[idx].irq[i]);
-    NVIC_SetPriority(sercomData[idx].irq[i], SERCOM_NVIC_PRIORITY);
-    NVIC_EnableIRQ(sercomData[idx].irq[i]);
+    NVIC_ClearPendingIRQ(SERCOM0_0_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM0_1_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM0_2_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM0_3_IRQn);
+
+    NVIC_SetPriority (SERCOM0_0_IRQn, (1<<__NVIC_PRIO_BITS) - 1);  /* set Priority */
+    NVIC_SetPriority (SERCOM0_1_IRQn, (1<<__NVIC_PRIO_BITS) - 1); 
+    NVIC_SetPriority (SERCOM0_2_IRQn, (1<<__NVIC_PRIO_BITS) - 1); 
+    NVIC_SetPriority (SERCOM0_3_IRQn, (1<<__NVIC_PRIO_BITS) - 1);
+
+    NVIC_EnableIRQ(SERCOM0_0_IRQn);
+    NVIC_EnableIRQ(SERCOM0_1_IRQn);
+    NVIC_EnableIRQ(SERCOM0_2_IRQn);
+    NVIC_EnableIRQ(SERCOM0_3_IRQn);
+	}
+	else if(sercom == SERCOM1)
+	{
+		clk_core = SERCOM1_GCLK_ID_CORE;
+		clk_slow = SERCOM1_GCLK_ID_SLOW;
+
+    NVIC_ClearPendingIRQ(SERCOM1_0_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM1_1_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM1_2_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM1_3_IRQn);
+
+    NVIC_SetPriority (SERCOM1_0_IRQn, (1<<__NVIC_PRIO_BITS) - 1);  /* set Priority */
+    NVIC_SetPriority (SERCOM1_1_IRQn, (1<<__NVIC_PRIO_BITS) - 1); 
+    NVIC_SetPriority (SERCOM1_2_IRQn, (1<<__NVIC_PRIO_BITS) - 1); 
+    NVIC_SetPriority (SERCOM1_3_IRQn, (1<<__NVIC_PRIO_BITS) - 1);
+
+    NVIC_EnableIRQ(SERCOM1_0_IRQn);
+    NVIC_EnableIRQ(SERCOM1_1_IRQn);
+    NVIC_EnableIRQ(SERCOM1_2_IRQn);
+    NVIC_EnableIRQ(SERCOM1_3_IRQn);
+	}
+	else if(sercom == SERCOM2)
+	{
+		clk_core = SERCOM2_GCLK_ID_CORE;
+		clk_slow = SERCOM2_GCLK_ID_SLOW;
+
+    NVIC_ClearPendingIRQ(SERCOM2_0_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM2_1_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM2_2_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM2_3_IRQn);
+
+    NVIC_SetPriority (SERCOM2_0_IRQn, (1<<__NVIC_PRIO_BITS) - 1);  /* set Priority */
+    NVIC_SetPriority (SERCOM2_1_IRQn, (1<<__NVIC_PRIO_BITS) - 1); 
+    NVIC_SetPriority (SERCOM2_2_IRQn, (1<<__NVIC_PRIO_BITS) - 1); 
+    NVIC_SetPriority (SERCOM2_3_IRQn, (1<<__NVIC_PRIO_BITS) - 1);
+
+    NVIC_EnableIRQ(SERCOM2_0_IRQn);
+    NVIC_EnableIRQ(SERCOM2_1_IRQn);
+    NVIC_EnableIRQ(SERCOM2_2_IRQn);
+    NVIC_EnableIRQ(SERCOM2_3_IRQn);
+	}
+	else if(sercom == SERCOM3)
+	{
+		clk_core = SERCOM3_GCLK_ID_CORE;
+		clk_slow = SERCOM3_GCLK_ID_SLOW;
+
+    NVIC_ClearPendingIRQ(SERCOM3_0_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM3_1_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM3_2_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM3_3_IRQn);
+
+    NVIC_SetPriority (SERCOM3_0_IRQn, (1<<__NVIC_PRIO_BITS) - 1);  /* set Priority */
+    NVIC_SetPriority (SERCOM3_1_IRQn, (1<<__NVIC_PRIO_BITS) - 1); 
+    NVIC_SetPriority (SERCOM3_2_IRQn, (1<<__NVIC_PRIO_BITS) - 1); 
+    NVIC_SetPriority (SERCOM3_3_IRQn, (1<<__NVIC_PRIO_BITS) - 1);
+
+    NVIC_EnableIRQ(SERCOM3_0_IRQn);
+    NVIC_EnableIRQ(SERCOM3_1_IRQn);
+    NVIC_EnableIRQ(SERCOM3_2_IRQn);
+    NVIC_EnableIRQ(SERCOM3_3_IRQn);
+	}
+	else if(sercom == SERCOM4)
+	{
+		clk_core = SERCOM4_GCLK_ID_CORE;
+		clk_slow = SERCOM4_GCLK_ID_SLOW;
+
+    NVIC_ClearPendingIRQ(SERCOM4_0_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM4_1_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM4_2_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM4_3_IRQn);
+
+    NVIC_SetPriority (SERCOM4_0_IRQn, (1<<__NVIC_PRIO_BITS) - 1);  /* set Priority */
+    NVIC_SetPriority (SERCOM4_1_IRQn, (1<<__NVIC_PRIO_BITS) - 1); 
+    NVIC_SetPriority (SERCOM4_2_IRQn, (1<<__NVIC_PRIO_BITS) - 1); 
+    NVIC_SetPriority (SERCOM4_3_IRQn, (1<<__NVIC_PRIO_BITS) - 1);
+
+    NVIC_EnableIRQ(SERCOM4_0_IRQn);
+    NVIC_EnableIRQ(SERCOM4_1_IRQn);
+    NVIC_EnableIRQ(SERCOM4_2_IRQn);
+    NVIC_EnableIRQ(SERCOM4_3_IRQn);
+	}
+	else if(sercom == SERCOM5)
+	{
+		clk_core = SERCOM5_GCLK_ID_CORE;
+		clk_slow = SERCOM5_GCLK_ID_SLOW;
+
+    NVIC_ClearPendingIRQ(SERCOM5_0_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM5_1_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM5_2_IRQn);
+    NVIC_ClearPendingIRQ(SERCOM5_3_IRQn);
+
+    NVIC_SetPriority (SERCOM5_0_IRQn, (1<<__NVIC_PRIO_BITS) - 1);  /* set Priority */
+    NVIC_SetPriority (SERCOM5_1_IRQn, (1<<__NVIC_PRIO_BITS) - 1); 
+    NVIC_SetPriority (SERCOM5_2_IRQn, (1<<__NVIC_PRIO_BITS) - 1); 
+    NVIC_SetPriority (SERCOM5_3_IRQn, (1<<__NVIC_PRIO_BITS) - 1);
+
+    NVIC_EnableIRQ(SERCOM5_0_IRQn);
+    NVIC_EnableIRQ(SERCOM5_1_IRQn);
+    NVIC_EnableIRQ(SERCOM5_2_IRQn);
+    NVIC_EnableIRQ(SERCOM5_3_IRQn);
+	}
+#else
+
+  IRQn_Type IdNvic=PendSV_IRQn ; // Dummy init to intercept potential error later
+
+  uint8_t clockId = 0;
+  if(sercom == SERCOM0)
+  {
+    clockId = GCM_SERCOM0_CORE;
+    IdNvic = SERCOM0_IRQn;
  }
+  else if(sercom == SERCOM1)
+  {
+    clockId = GCM_SERCOM1_CORE;
+    IdNvic = SERCOM1_IRQn;
+  }
+  else if(sercom == SERCOM2)
+  {
+    clockId = GCM_SERCOM2_CORE;
+    IdNvic = SERCOM2_IRQn;
+  }
+  else if(sercom == SERCOM3)
+  {
+    clockId = GCM_SERCOM3_CORE;
+    IdNvic = SERCOM3_IRQn;
+  }
+#if defined(SERCOM4)
+  else if(sercom == SERCOM4)
+  {
+    clockId = GCM_SERCOM4_CORE;
+    IdNvic = SERCOM4_IRQn;
+  }
+#endif
+#if defined(SERCOM5)
+  else if(sercom == SERCOM5)
+  {
+    clockId = GCM_SERCOM5_CORE;
+    IdNvic = SERCOM5_IRQn;
+  }
+#endif

-  // SPI DMA speed is dictated by the "slow clock" (I think...maybe) so
-  // BOTH are set to the same clock source (clk_slow isn't sourced from
-  // XOSC32K as in prior versions of SAMD core).
-  // This might have power implications for sleep code.
+  if ( IdNvic == PendSV_IRQn )
+  {
+    // We got a problem here
+    return ;
+  }
+#endif

-  setClockSource(idx, clockSource, true);  // true  = core clock
-  setClockSource(idx, clockSource, false); // false = slow clock
-
-#else // end if SAMD51 (prob SAMD21)
-
-  uint8_t   clockId = sercomData[idx].clock;
-  IRQn_Type IdNvic  = sercomData[idx].irqn;
-
-  // Setting NVIC
+#if defined(__SAMD51__)
+  GCLK->PCHCTRL[clk_core].reg = GCLK_PCHCTRL_GEN_GCLK1_Val | (1 << GCLK_PCHCTRL_CHEN_Pos);
+  GCLK->PCHCTRL[clk_slow].reg = GCLK_PCHCTRL_GEN_GCLK3_Val | (1 << GCLK_PCHCTRL_CHEN_Pos);
+  
+#else
+    // Setting NVIC
  NVIC_ClearPendingIRQ(IdNvic);
-  NVIC_SetPriority(IdNvic, SERCOM_NVIC_PRIORITY);
+  NVIC_SetPriority (IdNvic, (1<<__NVIC_PRIO_BITS) - 1);  /* set Priority */
  NVIC_EnableIRQ(IdNvic);

-  // Setting clock
-  GCLK->CLKCTRL.reg =
-    GCLK_CLKCTRL_ID( clockId ) | // Generic Clock 0 (SERCOMx)
-    GCLK_CLKCTRL_GEN_GCLK0     | // Generic Clock Generator 0 is source
-    GCLK_CLKCTRL_CLKEN;
+  //Setting clock
+  GCLK->CLKCTRL.reg = GCLK_CLKCTRL_ID( clockId ) | // Generic Clock 0 (SERCOMx)
+                      GCLK_CLKCTRL_GEN_GCLK0 | // Generic Clock Generator 0 is source
+                      GCLK_CLKCTRL_CLKEN ;

-  while(GCLK->STATUS.reg & GCLK_STATUS_SYNCBUSY); // Wait for synchronization
-
-#endif // end !SAMD51
+  while ( GCLK->STATUS.reg & GCLK_STATUS_SYNCBUSY )
+  {
+    /* Wait for synchronization */
+  }
+#endif
 }
--- a/cores/arduino/SERCOM.h
+++ b/cores/arduino/SERCOM.h
@ -21,19 +21,8 @@

 #include "sam.h"

-// SAMD51 has configurable MAX_SPI, else use peripheral clock default.
-// Update: changing MAX_SPI via compiler flags is DEPRECATED, because
-// this affects ALL SPI peripherals including some that should NOT be
-// changed (e.g. anything using SD card). Instead, use setClockSource().
-// This is left here for compatibility w/interim MAX_SPI-dependent code:
-#if defined(MAX_SPI)
-  #define SERCOM_SPI_FREQ_REF (MAX_SPI * 2)
-#else
-  #define SERCOM_SPI_FREQ_REF 48000000ul
-#endif
-// Other SERCOM peripherals always use the 48 MHz clock
-#define SERCOM_FREQ_REF       48000000ul
-#define SERCOM_NVIC_PRIORITY  ((1<<__NVIC_PRIO_BITS) - 1)
+#define SERCOM_FREQ_REF      48000000ul
+#define SERCOM_NVIC_PRIORITY ((1<<__NVIC_PRIO_BITS) - 1)

 typedef enum
 {
@ -91,23 +80,23 @@ typedef enum

 typedef enum
 {
-	UART_TX_PAD_0 = 0x0ul,  // Only for UART
+	UART_TX_PAD_0 = 0x0ul,	// Only for UART
 	UART_TX_PAD_2 = 0x1ul,  // Only for UART
 	UART_TX_RTS_CTS_PAD_0_2_3 = 0x2ul,  // Only for UART with TX on PAD0, RTS on PAD2 and CTS on PAD3
 } SercomUartTXPad;

 typedef enum
 {
-	SAMPLE_RATE_x16 = 0x1,  // Fractional
-	SAMPLE_RATE_x8  = 0x3,  // Fractional
+	SAMPLE_RATE_x16 = 0x1,	//Fractional
+	SAMPLE_RATE_x8 = 0x3,	//Fractional
 } SercomUartSampleRate;

 typedef enum
 {
-	SERCOM_SPI_MODE_0 = 0, // CPOL : 0 | CPHA : 0
-	SERCOM_SPI_MODE_1,     // CPOL : 0 | CPHA : 1
-	SERCOM_SPI_MODE_2,     // CPOL : 1 | CPHA : 0
-	SERCOM_SPI_MODE_3      // CPOL : 1 | CPHA : 1
+	SERCOM_SPI_MODE_0 = 0,	// CPOL : 0  | CPHA : 0
+	SERCOM_SPI_MODE_1,		// CPOL : 0  | CPHA : 1
+	SERCOM_SPI_MODE_2,		// CPOL : 1  | CPHA : 0
+	SERCOM_SPI_MODE_3		// CPOL : 1  | CPHA : 1
 } SercomSpiClockMode;

 typedef enum
@ -152,19 +141,6 @@ typedef enum
 	WIRE_MASTER_NACK_ACTION
 } SercomMasterAckActionWire;

-// SERCOM clock source override is available only on SAMD51 (not 21)
-// but the enumeration is made regardless so user code doesn't need
-// ifdefs or lengthy comments explaining the different situations --
-// the clock-sourcing functions just compile to nothing on SAMD21.
-typedef enum {
-  SERCOM_CLOCK_SOURCE_FCPU,     // F_CPU clock (GCLK0)
-  SERCOM_CLOCK_SOURCE_48M,      // 48 MHz peripheral clock (GCLK1) (standard)
-  SERCOM_CLOCK_SOURCE_100M,     // 100 MHz peripheral clock (GCLK2)
-  SERCOM_CLOCK_SOURCE_32K,      // XOSC32K clock (GCLK3)
-  SERCOM_CLOCK_SOURCE_12M,      // 12 MHz peripheral clock (GCLK4)
-  SERCOM_CLOCK_SOURCE_NO_CHANGE // Leave clock source setting unchanged
-} SercomClockSource;
-
 class SERCOM
 {
 	public:
@ -195,6 +171,7 @@ class SERCOM
 		/* ========== SPI ========== */
 		void initSPI(SercomSpiTXPad mosi, SercomRXPad miso, SercomSpiCharSize charSize, SercomDataOrder dataOrder) ;
 		void initSPIClock(SercomSpiClockMode clockMode, uint32_t baudrate) ;
+
 		void resetSPI( void ) ;
 		void enableSPI( void ) ;
 		void disableSPI( void ) ;
@ -225,9 +202,6 @@ class SERCOM
 		bool isSlaveWIRE( void ) ;
 		bool isBusIdleWIRE( void ) ;
 		bool isBusOwnerWIRE( void ) ;
-		bool isBusUnknownWIRE( void ) ;
-		bool isArbLostWIRE( void );
-		bool isBusBusyWIRE( void );
 		bool isDataReadyWIRE( void ) ;
 		bool isStopDetectedWIRE( void ) ;
 		bool isRestartDetectedWIRE( void ) ;
@ -236,30 +210,10 @@ class SERCOM
    bool isRXNackReceivedWIRE( void ) ;
 		int availableWIRE( void ) ;
 		uint8_t readDataWIRE( void ) ;
-		int8_t getSercomIndex(void);
-#if defined(__SAMD51__)
-		// SERCOM clock source override is only available on
-		// SAMD51 (not 21) ... but these functions are declared
-		// regardless so user code doesn't need ifdefs or lengthy
-		// comments explaining the different situations -- these
-		// just compile to nothing on SAMD21.
-		void setClockSource(int8_t idx, SercomClockSource src, bool core);
-		SercomClockSource getClockSource(void) { return clockSource; };
-		uint32_t getFreqRef(void) { return freqRef; };
-#else
-		// The equivalent SAMD21 dummy functions...
-		void setClockSource(int8_t idx, SercomClockSource src, bool core) { (void)idx; (void)src; (void)core; };
-		SercomClockSource getClockSource(void) { return SERCOM_CLOCK_SOURCE_FCPU; };
-		uint32_t getFreqRef(void) { return F_CPU; };
-#endif

 	private:
 		Sercom* sercom;
-#if defined(__SAMD51__)
-                SercomClockSource clockSource;
-                uint32_t freqRef; // Frequency corresponding to clockSource
-#endif
-		uint8_t calculateBaudrateSynchronous(uint32_t baudrate);
+		uint8_t calculateBaudrateSynchronous(uint32_t baudrate) ;
 		uint32_t division(uint32_t dividend, uint32_t divisor) ;
 		void initClockNVIC( void ) ;
 };
--- a/cores/arduino/Stream.cpp
+++ b/cores/arduino/Stream.cpp
@ -35,7 +35,6 @@ int Stream::timedRead()
  do {
    c = read();
    if (c >= 0) return c;
-    yield(); // running TinyUSB task
  } while(millis() - _startMillis < _timeout);
  return -1;     // -1 indicates timeout
 }
@ -48,7 +47,6 @@ int Stream::timedPeek()
  do {
    c = peek();
    if (c >= 0) return c;
-    yield(); // running TinyUSB task
  } while(millis() - _startMillis < _timeout);
  return -1;     // -1 indicates timeout
 }
--- a/cores/arduino/TinyUSB/Adafruit_TinyUSB_ArduinoCore
+++ b/cores/arduino/TinyUSB/Adafruit_TinyUSB_ArduinoCore
@ -1 +0,0 @@
-Subproject commit e7b892095f2bb5d8bef6a748238369bdd268ed5e
--- a/cores/arduino/TinyUSB/Adafruit_TinyUSB_SAMD.cpp
+++ b/cores/arduino/TinyUSB/Adafruit_TinyUSB_SAMD.cpp
@ -1,195 +0,0 @@
-/*
- * The MIT License (MIT)
- *
- * Copyright (c) 2019, hathach for Adafruit
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
-
-#ifdef USE_TINYUSB
-
-#include "Arduino.h"
-#include "Adafruit_TinyUSB_Core.h"
-#include <Reset.h> // Needed for auto-reset with 1200bps port touch
-
-//--------------------------------------------------------------------+
-// Forward USB interrupt events to TinyUSB IRQ Handler
-//--------------------------------------------------------------------+
-extern "C"
-{
-#if defined(__SAMD51__)
-
-void USB_0_Handler (void) { tud_int_handler(0); }
-void USB_1_Handler (void) { tud_int_handler(0); }
-void USB_2_Handler (void) { tud_int_handler(0); }
-void USB_3_Handler (void) { tud_int_handler(0); }
-
-#else
-
-void USB_Handler(void) { tud_int_handler(0); }
-
-#endif
-} // extern C
-
-
-
-//--------------------------------------------------------------------+
-// MACRO TYPEDEF CONSTANT ENUM DECLARATION
-//--------------------------------------------------------------------+
-static void usb_hardware_init(void);
-
-#if CFG_TUSB_DEBUG
-extern "C" int serial1_printf(const char *__restrict format, ...)
-{
-  char buf[PRINTF_BUF];
-  va_list ap;
-  va_start(ap, format);
-  vsnprintf(buf, sizeof(buf), format, ap);
-  Serial1.write(buf);
-  va_end(ap);
-
-}
-#endif
-
-//--------------------------------------------------------------------+
-// Core Init & Touch1200
-//--------------------------------------------------------------------+
-void Adafruit_TinyUSB_Core_init(void)
-{
-#if CFG_TUSB_DEBUG
-  Serial1.begin(115200);
-  serial1_printf("TinyUSB debugging with Serial1\n");
-#endif
-
-  Serial.setStringDescriptor("TinyUSB Serial");
-  USBDevice.addInterface(Serial);
-  USBDevice.setID(USB_VID, USB_PID);
-  USBDevice.begin();
-
-  usb_hardware_init();
-
-  // Init tinyusb stack
-  tusb_init();
-}
-
-void Adafruit_TinyUSB_Core_touch1200(void)
-{
-  initiateReset(250);
-}
-
-//--------------------------------------------------------------------+
-// Adafruit_USBD_Device platform dependent
-//--------------------------------------------------------------------+
-
-uint8_t Adafruit_USBD_Device::getSerialDescriptor(uint16_t* serial_str)
-{
-  enum { SERIAL_BYTE_LEN = 16 };
-
-#ifdef __SAMD51__
-  uint32_t* id_addresses[4] = {(uint32_t *) 0x008061FC, (uint32_t *) 0x00806010,
-                               (uint32_t *) 0x00806014, (uint32_t *) 0x00806018};
-#else // samd21
-  uint32_t* id_addresses[4] = {(uint32_t *) 0x0080A00C, (uint32_t *) 0x0080A040,
-                               (uint32_t *) 0x0080A044, (uint32_t *) 0x0080A048};
-
-#endif
-
-  uint8_t raw_id[SERIAL_BYTE_LEN];
-
-  for (int i=0; i<4; i++) {
-      for (int k=0; k<4; k++) {
-          raw_id[4 * i + (3 - k)] = (*(id_addresses[i]) >> k * 8) & 0xff;
-      }
-  }
-
-  static const char nibble_to_hex[16] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
-
-  for (unsigned int i = 0; i < sizeof(raw_id); i++) {
-    for (int j = 0; j < 2; j++) {
-      uint8_t nibble = (raw_id[i] >> (j * 4)) & 0xf;
-      // Strings are UTF-16-LE encoded.
-      serial_str[i * 2 + (1 - j)] = nibble_to_hex[nibble];
-    }
-  }
-
-  return sizeof(raw_id)*2;
-}
-
-//--------------------------------------------------------------------+
-// Helpers
-//--------------------------------------------------------------------+
-
-// Init usb hardware when starting up. Softdevice is not enabled yet
-static void usb_hardware_init(void)
-{
-#ifdef PIN_LED_TXL
-//	txLEDPulse = 0;
-	pinMode(PIN_LED_TXL, OUTPUT);
-	digitalWrite(PIN_LED_TXL, HIGH);
-#endif
-
-#ifdef PIN_LED_RXL
-//	rxLEDPulse = 0;
-	pinMode(PIN_LED_RXL, OUTPUT);
-	digitalWrite(PIN_LED_RXL, HIGH);
-#endif
-
-	/* Enable USB clock */
-#if defined(__SAMD51__)
-	MCLK->APBBMASK.reg |= MCLK_APBBMASK_USB;
-	MCLK->AHBMASK.reg |= MCLK_AHBMASK_USB;
-
-	// Set up the USB DP/DN pins
-	PORT->Group[0].PINCFG[PIN_PA24H_USB_DM].bit.PMUXEN = 1;
-	PORT->Group[0].PMUX[PIN_PA24H_USB_DM/2].reg &= ~(0xF << (4 * (PIN_PA24H_USB_DM & 0x01u)));
-	PORT->Group[0].PMUX[PIN_PA24H_USB_DM/2].reg |= MUX_PA24H_USB_DM << (4 * (PIN_PA24H_USB_DM & 0x01u));
-	PORT->Group[0].PINCFG[PIN_PA25H_USB_DP].bit.PMUXEN = 1;
-	PORT->Group[0].PMUX[PIN_PA25H_USB_DP/2].reg &= ~(0xF << (4 * (PIN_PA25H_USB_DP & 0x01u)));
-	PORT->Group[0].PMUX[PIN_PA25H_USB_DP/2].reg |= MUX_PA25H_USB_DP << (4 * (PIN_PA25H_USB_DP & 0x01u));
-
-
-	GCLK->PCHCTRL[USB_GCLK_ID].reg = GCLK_PCHCTRL_GEN_GCLK1_Val | (1 << GCLK_PCHCTRL_CHEN_Pos);
-
-	NVIC_SetPriority(USB_0_IRQn, 0UL);
-	NVIC_SetPriority(USB_1_IRQn, 0UL);
-	NVIC_SetPriority(USB_2_IRQn, 0UL);
-	NVIC_SetPriority(USB_3_IRQn, 0UL);
-#else
-	PM->APBBMASK.reg |= PM_APBBMASK_USB;
-
-	// Set up the USB DP/DN pins
-	PORT->Group[0].PINCFG[PIN_PA24G_USB_DM].bit.PMUXEN = 1;
-	PORT->Group[0].PMUX[PIN_PA24G_USB_DM/2].reg &= ~(0xF << (4 * (PIN_PA24G_USB_DM & 0x01u)));
-	PORT->Group[0].PMUX[PIN_PA24G_USB_DM/2].reg |= MUX_PA24G_USB_DM << (4 * (PIN_PA24G_USB_DM & 0x01u));
-	PORT->Group[0].PINCFG[PIN_PA25G_USB_DP].bit.PMUXEN = 1;
-	PORT->Group[0].PMUX[PIN_PA25G_USB_DP/2].reg &= ~(0xF << (4 * (PIN_PA25G_USB_DP & 0x01u)));
-	PORT->Group[0].PMUX[PIN_PA25G_USB_DP/2].reg |= MUX_PA25G_USB_DP << (4 * (PIN_PA25G_USB_DP & 0x01u));
-
-	// Put Generic Clock Generator 0 as source for Generic Clock Multiplexer 6 (USB reference)
-	GCLK->CLKCTRL.reg = GCLK_CLKCTRL_ID(6)     | // Generic Clock Multiplexer 6
-	GCLK_CLKCTRL_GEN_GCLK0 | // Generic Clock Generator 0 is source
-	GCLK_CLKCTRL_CLKEN;
-	while (GCLK->STATUS.bit.SYNCBUSY)
-	;
-
-	NVIC_SetPriority((IRQn_Type) USB_IRQn, 0UL);
-#endif
-}
-
-#endif // USE_TINYUSB
--- a/cores/arduino/TinyUSB/tusb_config.h
+++ b/cores/arduino/TinyUSB/tusb_config.h
@ -1,93 +0,0 @@
-/*
- * The MIT License (MIT)
- *
- * Copyright (c) 2018, hathach for Adafruit
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
-
-#ifndef _TUSB_CONFIG_H_
-#define _TUSB_CONFIG_H_
-
-#ifdef __cplusplus
- extern "C" {
-#endif
-
-//--------------------------------------------------------------------
-// COMMON CONFIGURATION
-//--------------------------------------------------------------------
-#ifdef __SAMD51__
-  #define CFG_TUSB_MCU                OPT_MCU_SAMD51
-#else
-  #define CFG_TUSB_MCU                OPT_MCU_SAMD21
-#endif
-
-#ifdef USE_TINYUSB
-  #define CFG_TUSB_RHPORT0_MODE       OPT_MODE_DEVICE
-#else
-  #define CFG_TUSB_RHPORT0_MODE       OPT_MODE_NONE
-#endif
-
-#define CFG_TUSB_OS                 OPT_OS_NONE
-
-#define CFG_TUSB_DEBUG              0
-#if CFG_TUSB_DEBUG
-  #define tu_printf                 serial1_printf
-  extern int serial1_printf(const char *__restrict __format, ...);
-#endif
-
-#define CFG_TUSB_MEM_SECTION
-#define CFG_TUSB_MEM_ALIGN          TU_ATTR_ALIGNED(4)
-
-//--------------------------------------------------------------------
-// DEVICE CONFIGURATION
-//--------------------------------------------------------------------
-
-#define CFG_TUD_ENDOINT0_SIZE       64
-
-//------------- CLASS -------------//
-#define CFG_TUD_CDC                 1
-#define CFG_TUD_MSC                 1
-#define CFG_TUD_HID                 1
-#define CFG_TUD_MIDI                1
-#define CFG_TUD_VENDOR              1
-
-// CDC FIFO size of TX and RX
-#define CFG_TUD_CDC_RX_BUFSIZE      256
-#define CFG_TUD_CDC_TX_BUFSIZE      256
-
-// MSC Buffer size of Device Mass storage
-#define CFG_TUD_MSC_BUFSIZE         512
-
-// HID buffer size Should be sufficient to hold ID (if any) + Data
-#define CFG_TUD_HID_BUFSIZE         64
-
-// MIDI FIFO size of TX and RX
-#define CFG_TUD_MIDI_RX_BUFSIZE     128
-#define CFG_TUD_MIDI_TX_BUFSIZE     128
-
-// Vendor FIFO size of TX and RX
-#define CFG_TUD_VENDOR_RX_BUFSIZE   64
-#define CFG_TUD_VENDOR_TX_BUFSIZE   64
-
-#ifdef __cplusplus
- }
-#endif
-
-#endif /* _TUSB_CONFIG_H_ */
--- a/cores/arduino/Tone.cpp
+++ b/cores/arduino/Tone.cpp
@ -20,6 +20,12 @@
 #include "Tone.h"
 #include "variant.h"

+#if defined(__SAMD51__) 
+#define WAIT_TC16_REGS_SYNC(x) while(x->COUNT16.SYNCBUSY.bit.ENABLE);
+#else
+#define WAIT_TC16_REGS_SYNC(x) while(x->COUNT16.STATUS.bit.SYNCBUSY);
+#endif
+
 uint32_t toneMaxFrequency = F_CPU / 2;
 uint32_t lastOutputPin = 0xFFFFFFFF;

@ -31,24 +37,22 @@ volatile bool toneIsActive = false;
 volatile bool firstTimeRunning = false;

 #if defined(__SAMD51__)
-  #define TONE_TC         TC0
-  #define TONE_TC_IRQn    TC0_IRQn
-  #define TONE_TC_GCLK_ID	TC0_GCLK_ID
-  #define Tone_Handler    TC0_Handler
-
-  #define WAIT_TC16_REGS_SYNC(x) while(x->COUNT16.SYNCBUSY.bit.ENABLE);
-
+#define TONE_TC         TC2
+#define TONE_TC_IRQn    TC2_IRQn
+#define TONE_TC_GCLK_ID	TC2_GCLK_ID
 #else
-  #define TONE_TC         TC5
-  #define TONE_TC_IRQn    TC5_IRQn
-  #define Tone_Handler    TC5_Handler
-
-  #define WAIT_TC16_REGS_SYNC(x) while(x->COUNT16.STATUS.bit.SYNCBUSY);
+#define TONE_TC         TC5
+#define TONE_TC_IRQn    TC5_IRQn
 #endif
-
 #define TONE_TC_TOP     0xFFFF
 #define TONE_TC_CHANNEL 0

+#if defined(__SAMD51__)
+void TC2_Handler (void) __attribute__ ((weak, alias("Tone_Handler")));
+#else
+void TC5_Handler (void) __attribute__ ((weak, alias("Tone_Handler")));
+#endif
+
 static inline void resetTC (Tc* TCx)
 {
  // Disable TCx
@ -68,14 +72,6 @@ void toneAccurateClock (uint32_t accurateSystemCoreClockFrequency)

 void tone (uint32_t outputPin, uint32_t frequency, uint32_t duration)
 {
-
-  // Avoid divide by zero error by calling 'noTone' instead
-  if (frequency == 0)
-  {
-    noTone(outputPin);
-    return;
-  }
-
  // Configure interrupt request
  NVIC_DisableIRQ(TONE_TC_IRQn);
  NVIC_ClearPendingIRQ(TONE_TC_IRQn);
@ -84,16 +80,19 @@ void tone (uint32_t outputPin, uint32_t frequency, uint32_t duration)
  {
    firstTimeRunning = true;
    
-    NVIC_SetPriority(TONE_TC_IRQn, 5);
+    NVIC_SetPriority(TONE_TC_IRQn, 0);

 #if defined(__SAMD51__)
-    GCLK->PCHCTRL[TONE_TC_GCLK_ID].reg = GCLK_PCHCTRL_GEN_GCLK0_Val | (1 << GCLK_PCHCTRL_CHEN_Pos);
+	GCLK->PCHCTRL[TONE_TC_GCLK_ID].reg = GCLK_PCHCTRL_GEN_GCLK0_Val | (1 << GCLK_PCHCTRL_CHEN_Pos);
 #else
    // Enable GCLK for TC4 and TC5 (timer counter input clock)
    GCLK->CLKCTRL.reg = (uint16_t) (GCLK_CLKCTRL_CLKEN | GCLK_CLKCTRL_GEN_GCLK0 | GCLK_CLKCTRL_ID(GCM_TC4_TC5));
    while (GCLK->STATUS.bit.SYNCBUSY);
 #endif
  }
+
+  //if it's a rest, set to 1Hz (below audio range)
+  frequency = (frequency > 0 ? frequency : 1);
  
  if (toneIsActive && (outputPin != lastOutputPin))
    noTone(lastOutputPin);
@ -137,7 +136,7 @@ void tone (uint32_t outputPin, uint32_t frequency, uint32_t duration)
    default: break;
  }

-  toggleCount = (duration > 0 ? frequency * duration * 2 / 1000UL : -1LL);
+  toggleCount = (duration > 0 ? frequency * duration * 2 / 1000UL : -1);

  resetTC(TONE_TC);

@ -180,19 +179,9 @@ void tone (uint32_t outputPin, uint32_t frequency, uint32_t duration)

 void noTone (uint32_t outputPin)
 {
-  /* 'tone' need to run at least once in order to enable GCLK for
-   * the timers used for the tone-functionality. If 'noTone' is called
-   * without ever calling 'tone' before then 'WAIT_TC16_REGS_SYNC(TCx)'
-   * will wait infinitely. The variable 'firstTimeRunning' is set the
-   * 1st time 'tone' is set so it can be used to detect wether or not
-   * 'tone' has been called before.
-   */
-  if(firstTimeRunning)
-  {
-    resetTC(TONE_TC);
-    digitalWrite(outputPin, LOW);
-    toneIsActive = false;
-  }
+  resetTC(TONE_TC);
+  digitalWrite(outputPin, LOW);
+  toneIsActive = false;
 }

 #ifdef __cplusplus
--- a/cores/arduino/USB/CDC.cpp
+++ b/cores/arduino/USB/CDC.cpp
@ -16,8 +16,6 @@
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

-#ifndef USE_TINYUSB
-
 #include <Arduino.h>
 #include <Reset.h> // Needed for auto-reset with 1200bps port touch

@ -152,7 +150,6 @@ void Serial_::begin(uint32_t /* baud_count */, uint8_t /* config */)

 void Serial_::end(void)
 {
-	memset((void*)&_usbLineInfo, 0, sizeof(_usbLineInfo));
 }

 int Serial_::available(void)
@ -262,5 +259,3 @@ Serial_::operator bool()
 Serial_ Serial(USBDevice);

 #endif
-
-#endif // USE_TINYUSB
--- a/cores/arduino/USB/PluggableUSB.cpp
+++ b/cores/arduino/USB/PluggableUSB.cpp
@ -17,8 +17,6 @@
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

-#ifndef USE_TINYUSB
-
 #include "USBAPI.h"
 #include "USBDesc.h"
 #include "USBCore.h"
@ -115,6 +113,4 @@ PluggableUSB_::PluggableUSB_() : lastIf(CDC_ACM_INTERFACE + CDC_INTERFACE_COUNT)
 }

 #endif
-#endif
-
-#endif // USE_TINYUSB
+#endif
--- a/cores/arduino/USB/SAMD21_USBDevice.cpp
+++ b/cores/arduino/USB/SAMD21_USBDevice.cpp
@ -5,7 +5,6 @@
 *      Author: deanm
 */

-#ifndef USE_TINYUSB

 #include "SAMD21_USBDevice.h"

@ -37,5 +36,3 @@ void USBDevice_SAMD21G18x::calibrate() {
    usb.PADCAL.bit.TRANSP = pad_transp;
    usb.PADCAL.bit.TRIM   = pad_trim;
 }
-
-#endif // USE_TINYUSB
--- a/cores/arduino/USB/SAMD21_USBDevice.h
+++ b/cores/arduino/USB/SAMD21_USBDevice.h
@ -237,7 +237,7 @@ public:
 		release();
 	}

-	virtual ~DoubleBufferedEPOutHandler() {
+	~DoubleBufferedEPOutHandler() {
 		free((void*)data0);
 		free((void*)data1);
 	}
--- a/cores/arduino/USB/SAMR21_USBDevice.h
+++ b/cores/arduino/USB/SAMR21_USBDevice.h
@ -24,174 +24,7 @@
 #include <stdio.h>
 #include <stdint.h>

-typedef uint8_t ep_t;

-class USBDevice_SAMR21G18x {
-public:
-	USBDevice_SAMR21G18x() : usb(USB->DEVICE) {
-		// Empty
-	}
-
-	// USB Device function mapping
-	// ---------------------------
-
-	// Reset USB Device
-	void reset();
-
-	// Enable
-	inline void enable()  { usb.CTRLA.bit.ENABLE = 1; }
-	inline void disable() { usb.CTRLA.bit.ENABLE = 0; }
-
-	// USB mode (device/host)
-	inline void setUSBDeviceMode() { usb.CTRLA.bit.MODE = USB_CTRLA_MODE_DEVICE_Val; }
-	inline void setUSBHostMode()   { usb.CTRLA.bit.MODE = USB_CTRLA_MODE_HOST_Val;   }
-
-	inline void runInStandby()   { usb.CTRLA.bit.RUNSTDBY = 1; }
-	inline void noRunInStandby() { usb.CTRLA.bit.RUNSTDBY = 0; }
-
-	// USB speed
-	inline void setFullSpeed()       { usb.CTRLB.bit.SPDCONF = USB_DEVICE_CTRLB_SPDCONF_FS_Val;   }
-	inline void setLowSpeed()        { usb.CTRLB.bit.SPDCONF = USB_DEVICE_CTRLB_SPDCONF_LS_Val;   }
-	inline void setHiSpeed()         { usb.CTRLB.bit.SPDCONF = USB_DEVICE_CTRLB_SPDCONF_HS_Val;   }
-	inline void setHiSpeedTestMode() { usb.CTRLB.bit.SPDCONF = USB_DEVICE_CTRLB_SPDCONF_HSTM_Val; }
-
-	// Authorize attach if Vbus is present
-	inline void attach() { usb.CTRLB.bit.DETACH = 0; }
-	inline void detach() { usb.CTRLB.bit.DETACH = 1; }
-
-	// USB Interrupts
-	inline bool isEndOfResetInterrupt()        { return usb.INTFLAG.bit.EORST; }
-	inline void ackEndOfResetInterrupt()       { usb.INTFLAG.reg = USB_DEVICE_INTFLAG_EORST; }
-	inline void enableEndOfResetInterrupt()    { usb.INTENSET.bit.EORST = 1; } 
-	inline void disableEndOfResetInterrupt()   { usb.INTENCLR.bit.EORST = 1; } 
-
-	inline bool isStartOfFrameInterrupt()      { return usb.INTFLAG.bit.SOF; }
-	inline void ackStartOfFrameInterrupt()     { usb.INTFLAG.reg = USB_DEVICE_INTFLAG_SOF; }
-	inline void enableStartOfFrameInterrupt()  { usb.INTENSET.bit.SOF = 1; }
-	inline void disableStartOfFrameInterrupt() { usb.INTENCLR.bit.SOF = 1; }
-
-	// USB Address
-	inline void setAddress(uint32_t addr)   { usb.DADD.bit.DADD = addr; usb.DADD.bit.ADDEN = 1; }
-	inline void unsetAddress()              { usb.DADD.bit.DADD = 0;    usb.DADD.bit.ADDEN = 0; }
-
-	// Frame number
-	inline uint16_t frameNumber() { return usb.FNUM.bit.FNUM; }
-
-	// Load calibration values
-	void calibrate();
-
-	// USB Device Endpoints function mapping
-	// -------------------------------------
-
-	// Config
-	inline void epBank0SetType(ep_t ep, uint8_t type) { usb.DeviceEndpoint[ep].EPCFG.bit.EPTYPE0 = type; }
-	inline void epBank1SetType(ep_t ep, uint8_t type) { usb.DeviceEndpoint[ep].EPCFG.bit.EPTYPE1 = type; }
-
-	// Interrupts
-	inline uint16_t epInterruptSummary() { return usb.EPINTSMRY.reg; }
-
-	inline bool epBank0IsSetupReceived(ep_t ep)     { return usb.DeviceEndpoint[ep].EPINTFLAG.bit.RXSTP; }
-	inline bool epBank0IsStalled(ep_t ep)           { return usb.DeviceEndpoint[ep].EPINTFLAG.bit.STALL0; }
-	inline bool epBank1IsStalled(ep_t ep)           { return usb.DeviceEndpoint[ep].EPINTFLAG.bit.STALL1; }
-	inline bool epBank0IsTransferComplete(ep_t ep)  { return usb.DeviceEndpoint[ep].EPINTFLAG.bit.TRCPT0; }
-	inline bool epBank1IsTransferComplete(ep_t ep)  { return usb.DeviceEndpoint[ep].EPINTFLAG.bit.TRCPT1; }
-
-	inline void epBank0AckSetupReceived(ep_t ep)    { usb.DeviceEndpoint[ep].EPINTFLAG.reg = USB_DEVICE_EPINTFLAG_RXSTP; }
-	inline void epBank0AckStalled(ep_t ep)          { usb.DeviceEndpoint[ep].EPINTFLAG.reg = USB_DEVICE_EPINTFLAG_STALL(1); }
-	inline void epBank1AckStalled(ep_t ep)          { usb.DeviceEndpoint[ep].EPINTFLAG.reg = USB_DEVICE_EPINTFLAG_STALL(2); }
-	inline void epBank0AckTransferComplete(ep_t ep) { usb.DeviceEndpoint[ep].EPINTFLAG.reg = USB_DEVICE_EPINTFLAG_TRCPT(1); }
-	inline void epBank1AckTransferComplete(ep_t ep) { usb.DeviceEndpoint[ep].EPINTFLAG.reg = USB_DEVICE_EPINTFLAG_TRCPT(2); }
-
-	inline void epBank0EnableSetupReceived(ep_t ep)    { usb.DeviceEndpoint[ep].EPINTENSET.bit.RXSTP = 1; }
-	inline void epBank0EnableStalled(ep_t ep)          { usb.DeviceEndpoint[ep].EPINTENSET.bit.STALL0 = 1; }
-	inline void epBank1EnableStalled(ep_t ep)          { usb.DeviceEndpoint[ep].EPINTENSET.bit.STALL1 = 1; }
-	inline void epBank0EnableTransferComplete(ep_t ep) { usb.DeviceEndpoint[ep].EPINTENSET.bit.TRCPT0 = 1; }
-	inline void epBank1EnableTransferComplete(ep_t ep) { usb.DeviceEndpoint[ep].EPINTENSET.bit.TRCPT1 = 1; }
-
-	inline void epBank0DisableSetupReceived(ep_t ep)    { usb.DeviceEndpoint[ep].EPINTENCLR.bit.RXSTP = 1; }
-	inline void epBank0DisableStalled(ep_t ep)          { usb.DeviceEndpoint[ep].EPINTENCLR.bit.STALL0 = 1; }
-	inline void epBank1DisableStalled(ep_t ep)          { usb.DeviceEndpoint[ep].EPINTENCLR.bit.STALL1 = 1; }
-	inline void epBank0DisableTransferComplete(ep_t ep) { usb.DeviceEndpoint[ep].EPINTENCLR.bit.TRCPT0 = 1; }
-	inline void epBank1DisableTransferComplete(ep_t ep) { usb.DeviceEndpoint[ep].EPINTENCLR.bit.TRCPT1 = 1; }
-
-	// Status
-	inline bool epBank0IsReady(ep_t ep)    { return usb.DeviceEndpoint[ep].EPSTATUS.bit.BK0RDY; }
-	inline bool epBank1IsReady(ep_t ep)    { return usb.DeviceEndpoint[ep].EPSTATUS.bit.BK1RDY; }
-	inline void epBank0SetReady(ep_t ep)   { usb.DeviceEndpoint[ep].EPSTATUSSET.bit.BK0RDY = 1; }
-	inline void epBank1SetReady(ep_t ep)   { usb.DeviceEndpoint[ep].EPSTATUSSET.bit.BK1RDY = 1; }
-	inline void epBank0ResetReady(ep_t ep) { usb.DeviceEndpoint[ep].EPSTATUSCLR.bit.BK0RDY = 1; }
-	inline void epBank1ResetReady(ep_t ep) { usb.DeviceEndpoint[ep].EPSTATUSCLR.bit.BK1RDY = 1; }
-
-	inline void epBank0SetStallReq(ep_t ep)   { usb.DeviceEndpoint[ep].EPSTATUSSET.bit.STALLRQ0 = 1; }
-	inline void epBank1SetStallReq(ep_t ep)   { usb.DeviceEndpoint[ep].EPSTATUSSET.bit.STALLRQ1 = 1; }
-	inline void epBank0ResetStallReq(ep_t ep) { usb.DeviceEndpoint[ep].EPSTATUSCLR.bit.STALLRQ0 = 1; }
-	inline void epBank1ResetStallReq(ep_t ep) { usb.DeviceEndpoint[ep].EPSTATUSCLR.bit.STALLRQ1 = 1; }
-
-	// Packet
-	inline uint16_t epBank0ByteCount(ep_t ep) { return EP[ep].DeviceDescBank[0].PCKSIZE.bit.BYTE_COUNT; }
-	inline uint16_t epBank1ByteCount(ep_t ep) { return EP[ep].DeviceDescBank[1].PCKSIZE.bit.BYTE_COUNT; }
-	inline void epBank0SetByteCount(ep_t ep, uint16_t bc) { EP[ep].DeviceDescBank[0].PCKSIZE.bit.BYTE_COUNT = bc; }
-	inline void epBank1SetByteCount(ep_t ep, uint16_t bc) { EP[ep].DeviceDescBank[1].PCKSIZE.bit.BYTE_COUNT = bc; }
-	inline void epBank0SetMultiPacketSize(ep_t ep, uint16_t s) { EP[ep].DeviceDescBank[0].PCKSIZE.bit.MULTI_PACKET_SIZE = s; }
-	inline void epBank1SetMultiPacketSize(ep_t ep, uint16_t s) { EP[ep].DeviceDescBank[1].PCKSIZE.bit.MULTI_PACKET_SIZE = s; }
-
-	inline void epBank0SetAddress(ep_t ep, void *addr) { EP[ep].DeviceDescBank[0].ADDR.reg = (uint32_t)addr; }
-	inline void epBank1SetAddress(ep_t ep, void *addr) { EP[ep].DeviceDescBank[1].ADDR.reg = (uint32_t)addr; }
-	inline void epBank0SetSize(ep_t ep, uint16_t size) { EP[ep].DeviceDescBank[0].PCKSIZE.bit.SIZE = EP_PCKSIZE_SIZE(size); }
-	inline void epBank1SetSize(ep_t ep, uint16_t size) { EP[ep].DeviceDescBank[1].PCKSIZE.bit.SIZE = EP_PCKSIZE_SIZE(size); }
-	inline uint8_t EP_PCKSIZE_SIZE(uint16_t size) {
-		switch (size) {
-		case 8:    return 0;
-		case 16:   return 1;
-		case 32:   return 2;
-		case 64:   return 3;
-		case 128:  return 4;
-		case 256:  return 5;
-		case 512:  return 6;
-		case 1023: return 7;
-		default:   return 0;
-		}
-	}
-
-	inline void epBank0DisableAutoZLP(ep_t ep) { EP[ep].DeviceDescBank[0].PCKSIZE.bit.AUTO_ZLP = 0; }
-	inline void epBank1DisableAutoZLP(ep_t ep) { EP[ep].DeviceDescBank[1].PCKSIZE.bit.AUTO_ZLP = 0; }
-	inline void epBank0EnableAutoZLP(ep_t ep)  { EP[ep].DeviceDescBank[0].PCKSIZE.bit.AUTO_ZLP = 1; }
-	inline void epBank1EnableAutoZLP(ep_t ep)  { EP[ep].DeviceDescBank[1].PCKSIZE.bit.AUTO_ZLP = 1; }
-
-private:
-	// USB Device registers
-	UsbDevice &usb;
-
-	// Endpoints descriptors table
-	__attribute__((__aligned__(4)))	UsbDeviceDescriptor EP[USB_EPT_NUM];
-};
-
-void USBDevice_SAMR21G18x::reset() {
-	usb.CTRLA.bit.SWRST = 1;
-	memset(EP, 0, sizeof(EP));
-	while (usb.SYNCBUSY.bit.SWRST) {}
-	usb.DESCADD.reg = (uint32_t)(&EP);
-}
-
-void USBDevice_SAMR21G18x::calibrate() {
-	// Load Pad Calibration data from non-volatile memory
-	uint32_t *pad_transn_p = (uint32_t *) USB_FUSES_TRANSN_ADDR;
-	uint32_t *pad_transp_p = (uint32_t *) USB_FUSES_TRANSP_ADDR;
-	uint32_t *pad_trim_p   = (uint32_t *) USB_FUSES_TRIM_ADDR;
-
-	uint32_t pad_transn = (*pad_transn_p & USB_FUSES_TRANSN_Msk) >> USB_FUSES_TRANSN_Pos;
-	uint32_t pad_transp = (*pad_transp_p & USB_FUSES_TRANSP_Msk) >> USB_FUSES_TRANSP_Pos;
-	uint32_t pad_trim   = (*pad_trim_p   & USB_FUSES_TRIM_Msk  ) >> USB_FUSES_TRIM_Pos;
-
-	if (pad_transn == 0x1F)  // maximum value (31)
-		pad_transn = 5;
-	if (pad_transp == 0x1F)  // maximum value (31)
-		pad_transp = 29;
-	if (pad_trim == 0x7)     // maximum value (7)
-		pad_trim = 3;
-
-	usb.PADCAL.bit.TRANSN = pad_transn;
-	usb.PADCAL.bit.TRANSP = pad_transp;
-	usb.PADCAL.bit.TRIM   = pad_trim;
-}
+#include "SAMD21_USBDevice.h"

+typedef class USBDevice_SAMD21G18x USBDevice_SAMR21G18x;
--- a/cores/arduino/USB/USBAPI.h
+++ b/cores/arduino/USB/USBAPI.h
@ -65,7 +65,6 @@ public:

 	// USB Device API
 	void init();
-	bool end();
 	bool attach();
 	bool detach();
 	void setAddress(uint32_t addr);
--- a/cores/arduino/USB/USBCore.cpp
+++ b/cores/arduino/USB/USBCore.cpp
@ -16,7 +16,7 @@
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
-#ifndef USE_TINYUSB
+
 #if defined(USBCON)

 #include <Arduino.h>
@ -244,25 +244,26 @@ bool USBDeviceClass::sendDescriptor(USBSetup &setup)
 		}
 		else if (setup.wValueL == ISERIAL) {
 #ifdef PLUGGABLE_USB_ENABLED
-#ifdef __SAMD51__
-			#define SERIAL_NUMBER_WORD_0	*(volatile uint32_t*)(0x008061FC)
-			#define SERIAL_NUMBER_WORD_1	*(volatile uint32_t*)(0x00806010)
-			#define SERIAL_NUMBER_WORD_2	*(volatile uint32_t*)(0x00806014)
-			#define SERIAL_NUMBER_WORD_3	*(volatile uint32_t*)(0x00806018)
-#else // samd21
+#if defined(__SAMD51__)
+			char name[ISERIAL_MAX_LEN];
+			PluggableUSB().getShortName(name);
+			return sendStringDescriptor((uint8_t*)name, setup.wLength);
+#else
 			// from section 9.3.3 of the datasheet
 			#define SERIAL_NUMBER_WORD_0	*(volatile uint32_t*)(0x0080A00C)
 			#define SERIAL_NUMBER_WORD_1	*(volatile uint32_t*)(0x0080A040)
 			#define SERIAL_NUMBER_WORD_2	*(volatile uint32_t*)(0x0080A044)
 			#define SERIAL_NUMBER_WORD_3	*(volatile uint32_t*)(0x0080A048)
-#endif
+
 			char name[ISERIAL_MAX_LEN];
 			utox8(SERIAL_NUMBER_WORD_0, &name[0]);
 			utox8(SERIAL_NUMBER_WORD_1, &name[8]);
 			utox8(SERIAL_NUMBER_WORD_2, &name[16]);
 			utox8(SERIAL_NUMBER_WORD_3, &name[24]);
-			name[32] = '\0';
+
+			PluggableUSB().getShortName(&name[32]);
 			return sendStringDescriptor((uint8_t*)name, setup.wLength);
+#endif
 #endif
 		}
 		else {
@ -433,13 +434,6 @@ bool USBDeviceClass::detach()
 	return true;
 }

-bool USBDeviceClass::end() {
-	if (!initialized)
-		return false;
-	usbd.disable();
-	return true;
-}
-
 bool USBDeviceClass::configured()
 {
 	return _usbConfiguration != 0;
@ -877,7 +871,6 @@ bool USBDeviceClass::handleStandardSetup(USBSetup &setup)
 			sendZlp(0);
 			return true;
 		}
-		return false;

 	case SET_ADDRESS:
 		setAddress(setup.wValueL);
@ -1039,4 +1032,3 @@ void USBDeviceClass::ISRHandler()
 USBDeviceClass USBDevice;

 #endif
-#endif // USE_TINYUSB
--- a/cores/arduino/USB/USBCore.h
+++ b/cores/arduino/USB/USBCore.h
@ -101,7 +101,7 @@
 // bMaxPower in Configuration Descriptor
 #define USB_CONFIG_POWER_MA(mA)                ((mA)/2)
 #ifndef USB_CONFIG_POWER
- #define USB_CONFIG_POWER                      (100)
+ #define USB_CONFIG_POWER                      (500)
 #endif

 #define CDC_V1_10                               0x0110
--- a/cores/arduino/USB/samd21_host.c
+++ b/cores/arduino/USB/samd21_host.c
@ -17,7 +17,6 @@
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

-#ifndef USE_TINYUSB

 #include <stdio.h>
 #include <stdint.h>
@ -64,6 +63,7 @@ void UHD_Init(void)
 	uint32_t pad_transn;
 	uint32_t pad_transp;
 	uint32_t pad_trim;
+	uint32_t i;

 	USB_SetHandler(&UHD_Handler);

@ -172,7 +172,10 @@ void UHD_Init(void)
 	USB->HOST.DESCADD.reg = (uint32_t)(&usb_pipe_table[0]);
 	// For USB_SPEED_FULL
 	uhd_force_full_speed();
-	memset((void *)usb_pipe_table, 0, sizeof(usb_pipe_table));
+	for (i = 0; i < sizeof(usb_pipe_table); i++)
+	{
+		(*(uint32_t *)(&usb_pipe_table[0] + i)) = 0;
+	}

 	uhd_state = UHD_STATE_NO_VBUS;

@ -554,5 +557,3 @@ uint32_t UHD_Pipe_Is_Transfer_Complete(uint32_t ul_pipe, uint32_t ul_token_type)
 // }

 #endif //  HOST_DEFINED
-
-#endif // USE_TINYUSB
--- a/cores/arduino/WInterrupts.c
+++ b/cores/arduino/WInterrupts.c
@ -78,129 +78,133 @@ static void __initialize()
 */
 void attachInterrupt(uint32_t pin, voidFuncPtr callback, uint32_t mode)
 {
-	static int enabled = 0;
-	uint32_t config;
-	uint32_t pos;
+  static int enabled = 0;
+  uint32_t config;
+  uint32_t pos;

-	#if ARDUINO_SAMD_VARIANT_COMPLIANCE >= 10606
-	EExt_Interrupts in = g_APinDescription[pin].ulExtInt;
-	#else
-	EExt_Interrupts in = digitalPinToInterrupt(pin);
-	#endif
-	if (in == NOT_AN_INTERRUPT) return;
+#if ARDUINO_SAMD_VARIANT_COMPLIANCE >= 10606
+  EExt_Interrupts in = g_APinDescription[pin].ulExtInt;
+#else
+  EExt_Interrupts in = digitalPinToInterrupt(pin);
+#endif
+  if (in == NOT_AN_INTERRUPT) return;

-	if (!enabled) {
-		__initialize();
-		enabled = 1;
-	}
-	uint32_t inMask = (1UL << in);
-	// Enable wakeup capability on pin in case being used during sleep
-	#if defined(__SAMD51__)
-	//I believe this is done automatically
-	#else
-	EIC->WAKEUP.reg |= (1 << in);
-	#endif
+  if (!enabled) {
+    __initialize();
+    enabled = 1;
+  }

-	// Only store when there is really an ISR to call.
-	// This allow for calling attachInterrupt(pin, NULL, mode), we set up all needed register
-	// but won't service the interrupt, this way we also don't need to check it inside the ISR.
-	if (callback)
-	{
-		if (in == EXTERNAL_INT_NMI) {
-			EIC->NMIFLAG.bit.NMI = 1; // Clear flag
-			switch (mode) {
-			  case LOW:
-				EIC->NMICTRL.bit.NMISENSE = EIC_NMICTRL_NMISENSE_LOW;
-				break;
+  // Only store when there is really an ISR to call.
+  // This allow for calling attachInterrupt(pin, NULL, mode), we set up all needed register
+  // but won't service the interrupt, this way we also don't need to check it inside the ISR.
+  if (callback)
+  {
+    // Store interrupts to service in order of when they were attached
+    // to allow for first come first serve handler
+    uint32_t current = 0;
+    uint32_t inMask = (1UL << in);

-			  case HIGH:
-				EIC->NMICTRL.bit.NMISENSE = EIC_NMICTRL_NMISENSE_HIGH;
-				break;
+    // Check if we already have this interrupt
+    for (current=0; current<nints; current++) {
+      if (ISRlist[current] == inMask) {
+        break;
+      }
+    }
+    if (current == nints) {
+      // Need to make a new entry
+      nints++;
+    }
+    ISRlist[current] = inMask;       // List of interrupt in order of when they were attached
+    ISRcallback[current] = callback; // List of callback adresses
+  }

-			  case CHANGE:
-				EIC->NMICTRL.bit.NMISENSE = EIC_NMICTRL_NMISENSE_BOTH;
-				break;
+  if (in == EXTERNAL_INT_NMI) {
+    EIC->NMIFLAG.bit.NMI = 1; // Clear flag
+    switch (mode) {
+      case LOW:
+        EIC->NMICTRL.bit.NMISENSE = EIC_NMICTRL_NMISENSE_LOW;
+        break;

-			  case FALLING:
-				EIC->NMICTRL.bit.NMISENSE = EIC_NMICTRL_NMISENSE_FALL;
-				break;
+      case HIGH:
+        EIC->NMICTRL.bit.NMISENSE = EIC_NMICTRL_NMISENSE_HIGH;
+        break;

-			  case RISING:
-				EIC->NMICTRL.bit.NMISENSE = EIC_NMICTRL_NMISENSE_RISE;
-				break;
-			}
+      case CHANGE:
+        EIC->NMICTRL.bit.NMISENSE = EIC_NMICTRL_NMISENSE_BOTH;
+        break;

-			// Assign callback to interrupt
-			ISRcallback[EXTERNAL_INT_NMI] = callback;
+      case FALLING:
+        EIC->NMICTRL.bit.NMISENSE = EIC_NMICTRL_NMISENSE_FALL;
+        break;

-		} else { // Not NMI, is external interrupt
+      case RISING:
+        EIC->NMICTRL.bit.NMISENSE = EIC_NMICTRL_NMISENSE_RISE;
+        break;
+    }

-			// Assign pin to EIC
-			pinPeripheral(pin, PIO_EXTINT);
+    // Assign callback to interrupt
+    ISRcallback[EXTERNAL_INT_NMI] = callback;

-			// Store interrupts to service in order of when they were attached
-			// to allow for first come first serve handler
-			uint32_t current = 0;
+  } else { // Not NMI, is external interrupt

-			// Check if we already have this interrupt
-			for (current=0; current<nints; current++) {
-			  if (ISRlist[current] == inMask) {
-				break;
-			  }
-			}
-			if (current == nints) {
-			  // Need to make a new entry
-			  nints++;
-			}
-			ISRlist[current] = inMask;       // List of interrupt in order of when they were attached
-			ISRcallback[current] = callback; // List of callback adresses
+    // Enable wakeup capability on pin in case being used during sleep
+#if defined(__SAMD51__)
+//I believe this is done automatically
+#else
+    EIC->WAKEUP.reg |= (1 << in);
+#endif

-			// Look for right CONFIG register to be addressed
-			if (in > EXTERNAL_INT_7) {
-			  config = 1;
-			  pos = (in - 8) << 2;
-			} else {
-			  config = 0;
-			  pos = in << 2;
-			}
+    // Assign pin to EIC
+    pinPeripheral(pin, PIO_EXTINT);

-			#if defined (__SAMD51__)
-			EIC->CTRLA.bit.ENABLE = 0;
-			while (EIC->SYNCBUSY.bit.ENABLE == 1) { }
-			#endif
+    // Assign callback to interrupt
+    ISRcallback[in] = callback;

-			EIC->CONFIG[config].reg &=~ (EIC_CONFIG_SENSE0_Msk << pos); // Reset sense mode, important when changing trigger mode during runtime
-			switch (mode)
-			{
-			  case LOW:
-				EIC->CONFIG[config].reg |= EIC_CONFIG_SENSE0_LOW_Val << pos;
-				break;
+    // Look for right CONFIG register to be addressed
+    if (in > EXTERNAL_INT_7) {
+      config = 1;
+    } else {
+      config = 0;
+    }

-			  case HIGH:
-				EIC->CONFIG[config].reg |= EIC_CONFIG_SENSE0_HIGH_Val << pos;
-				break;
+    // Configure the interrupt mode
+    pos = (in - (8 * config)) << 2;

-			  case CHANGE:
-				EIC->CONFIG[config].reg |= EIC_CONFIG_SENSE0_BOTH_Val << pos;
-				break;
+#if defined (__SAMD51__)
+  EIC->CTRLA.bit.ENABLE = 0;
+  while (EIC->SYNCBUSY.bit.ENABLE == 1) { }
+#endif

-			  case FALLING:
-				EIC->CONFIG[config].reg |= EIC_CONFIG_SENSE0_FALL_Val << pos;
-				break;
+    switch (mode)
+    {
+      case LOW:
+        EIC->CONFIG[config].reg |= EIC_CONFIG_SENSE0_LOW_Val << pos;
+        break;

-			  case RISING:
-				EIC->CONFIG[config].reg |= EIC_CONFIG_SENSE0_RISE_Val << pos;
-				break;
-			}
-		}
-		// Enable the interrupt
-		EIC->INTENSET.reg = EIC_INTENSET_EXTINT(1 << in);
-	}
+      case HIGH:
+        EIC->CONFIG[config].reg |= EIC_CONFIG_SENSE0_HIGH_Val << pos;
+        break;

-	#if defined (__SAMD51__)
-	EIC->CTRLA.bit.ENABLE = 1;
-	while (EIC->SYNCBUSY.bit.ENABLE == 1) { }
-	#endif
+      case CHANGE:
+        EIC->CONFIG[config].reg |= EIC_CONFIG_SENSE0_BOTH_Val << pos;
+        break;
+
+      case FALLING:
+        EIC->CONFIG[config].reg |= EIC_CONFIG_SENSE0_FALL_Val << pos;
+        break;
+
+      case RISING:
+        EIC->CONFIG[config].reg |= EIC_CONFIG_SENSE0_RISE_Val << pos;
+        break;
+    }
+  }
+  // Enable the interrupt
+  EIC->INTENSET.reg = EIC_INTENSET_EXTINT(1 << in);
+  
+#if defined (__SAMD51__)
+  EIC->CTRLA.bit.ENABLE = 1;
+  while (EIC->SYNCBUSY.bit.ENABLE == 1) { }
+#endif
 }

 /*
@ -250,22 +254,17 @@ void detachInterrupt(uint32_t pin)
 * External Interrupt Controller NVIC Interrupt Handler
 */
 #if defined(__SAMD51__)
-void InterruptHandler(uint32_t unused_i)
+void InterruptHandler(uint32_t i)
 {
-  (void)unused_i;
-  // Calling the routine directly from -here- takes about 1us
-  // Depending on where you are in the list it will take longer
-
-  // Loop over all enabled interrupts in the list
-  for (uint32_t i=0; i<nints; i++)
+  if ((EIC->INTFLAG.reg & (1 << i)) != 0)
  {
-	if ((EIC->INTFLAG.reg & ISRlist[i]) != 0)
-	{
-	  // Call the callback function
-	  ISRcallback[i]();
-	  // Clear the interrupt
-	  EIC->INTFLAG.reg = ISRlist[i];
-	}
+    // Call the callback function if assigned
+    if (ISRcallback[i]) {
+      ISRcallback[i]();
+    }
+
+    // Clear the interrupt
+    EIC->INTFLAG.reg = 1 << i;
  }
 }

@ -376,4 +375,4 @@ void NMI_Handler(void)
  if (ISRcallback[EXTERNAL_INT_NMI]) ISRcallback[EXTERNAL_INT_NMI]();
  EIC->NMIFLAG.bit.NMI = 1; // Clear interrupt
 }
-#endif
+#endif
--- a/cores/arduino/WInterrupts.h
+++ b/cores/arduino/WInterrupts.h
@ -31,7 +31,7 @@ extern "C" {
 #define FALLING 3
 #define RISING 4

-//#define DEFAULT 1
+#define DEFAULT 1
 #define EXTERNAL 0

 typedef void (*voidFuncPtr)(void);
--- a/cores/arduino/WVariant.h
+++ b/cores/arduino/WVariant.h
@ -57,41 +57,10 @@ typedef enum _EAnalogChannel
  ADC_Channel19=19,
  DAC_Channel0,
  DAC_Channel1,
-  ADC_Channel_Bandgap=0x1B,
-  ADC_Channel_PTAT=0x1C,
 } EAnalogChannel ;

 #if defined(__SAMD51__)

-#if defined(__SAMD51G19A__)
-
-typedef enum _ETCChannel
-{
-  NOT_ON_TIMER=-1,
-  TCC0_CH0 = (0<<8)|(0),
-  TCC0_CH1 = (0<<8)|(1),
-  TCC0_CH2 = (0<<8)|(2),
-  TCC0_CH3 = (0<<8)|(3),
-  TCC0_CH4 = (0<<8)|(4),
-  TCC0_CH5 = (0<<8)|(5),
-  TCC1_CH0 = (1<<8)|(0),
-  TCC1_CH1 = (1<<8)|(1),
-  TCC1_CH2 = (1<<8)|(2),
-  TCC1_CH3 = (1<<8)|(3),
-  TCC2_CH0 = (2<<8)|(0),
-  TCC2_CH1 = (2<<8)|(1),
-  TCC2_CH2 = (2<<8)|(2),
-  TC0_CH0 =  (3<<8)|(0),
-  TC0_CH1 =  (3<<8)|(1),
-  TC1_CH0 =  (4<<8)|(0),
-  TC1_CH1 =  (4<<8)|(1),
-  TC2_CH0 =  (5<<8)|(0),
-  TC2_CH1 =  (5<<8)|(1),
-  TC3_CH0 =  (6<<8)|(0),
-  TC3_CH1 =  (6<<8)|(1),
-} ETCChannel ;
-#elif defined(__SAMD51J19A__) || defined(__SAMD51J20A__)
-
 typedef enum _ETCChannel
 {
  NOT_ON_TIMER=-1,
@ -107,82 +76,12 @@ typedef enum _ETCChannel
  TCC1_CH1 = (1<<8)|(1),
  TCC1_CH2 = (1<<8)|(2),
  TCC1_CH3 = (1<<8)|(3),
-  TCC1_CH4 = (1<<8)|(4),
-  TCC1_CH5 = (1<<8)|(5),
-  TCC1_CH6 = (1<<8)|(6),
-  TCC1_CH7 = (1<<8)|(7),
-  TCC2_CH0 = (2<<8)|(0),
-  TCC2_CH1 = (2<<8)|(1),
-  TCC2_CH2 = (2<<8)|(2),
-  TCC3_CH0 = (3<<8)|(0),
-  TCC3_CH1 = (3<<8)|(1),
-  TCC4_CH0 = (4<<8)|(0),
-  TCC4_CH1 = (4<<8)|(1),
-  TC0_CH0 =  (5<<8)|(0),
-  TC0_CH1 =  (5<<8)|(1),
-  TC1_CH0 =  (6<<8)|(0),
-  TC1_CH1 =  (6<<8)|(1),
-  TC2_CH0 =  (7<<8)|(0),
-  TC2_CH1 =  (7<<8)|(1),
-  TC3_CH0 =  (8<<8)|(0),
-  TC3_CH1 =  (8<<8)|(1),
-  TC4_CH0 =  (9<<8)|(0),
-  TC4_CH1 =  (9<<8)|(1),
-  TC5_CH0 =  (10<<8)|(0),
-  TC5_CH1 =  (10<<8)|(1),
-  TC6_CH0 =  (11<<8)|(0),
-  TC6_CH1 =  (11<<8)|(1),
-  TC7_CH0 =  (12<<8)|(0),
-  TC7_CH1 =  (12<<8)|(1),
+  TCC1_CH4 = (1<<8)|(0),
+  TCC1_CH5 = (1<<8)|(1),
+  TCC1_CH6 = (1<<8)|(2),
+  TCC1_CH7 = (1<<8)|(3),
 } ETCChannel ;

-#elif defined(__SAMD51P19A__) || defined(__SAMD51P20A__)
-
-typedef enum _ETCChannel
-{
-  NOT_ON_TIMER=-1,
-  TCC0_CH0 = (0<<8)|(0),
-  TCC0_CH1 = (0<<8)|(1),
-  TCC0_CH2 = (0<<8)|(2),
-  TCC0_CH3 = (0<<8)|(3),
-  TCC0_CH4 = (0<<8)|(4),
-  TCC0_CH5 = (0<<8)|(5),
-  TCC1_CH0 = (1<<8)|(0),
-  TCC1_CH1 = (1<<8)|(1),
-  TCC1_CH2 = (1<<8)|(2),
-  TCC1_CH3 = (1<<8)|(3),
-  TCC2_CH0 = (2<<8)|(0),
-  TCC2_CH1 = (2<<8)|(1),
-  TCC2_CH2 = (2<<8)|(2),
-  TCC3_CH0 = (3<<8)|(0),
-  TCC3_CH1 = (3<<8)|(1),
-  TCC4_CH0 = (4<<8)|(0),
-  TCC4_CH1 = (4<<8)|(1),
-  TC0_CH0 =  (5<<8)|(0),
-  TC0_CH1 =  (5<<8)|(1),
-  TC1_CH0 =  (6<<8)|(0),
-  TC1_CH1 =  (6<<8)|(1),
-  TC2_CH0 =  (7<<8)|(0),
-  TC2_CH1 =  (7<<8)|(1),
-  TC3_CH0 =  (8<<8)|(0),
-  TC3_CH1 =  (8<<8)|(1),
-  TC4_CH0 =  (9<<8)|(0),
-  TC4_CH1 =  (9<<8)|(1),
-  TC5_CH0 =  (10<<8)|(0),
-  TC5_CH1 =  (10<<8)|(1),
-  TC6_CH0 =  (11<<8)|(0),
-  TC6_CH1 =  (11<<8)|(1),
-  TC7_CH0 =  (12<<8)|(0),
-  TC7_CH1 =  (12<<8)|(1),
-} ETCChannel ;
-
-#endif
-
-typedef ETCChannel EPWMChannel;
-extern const uint32_t GCLK_CLKCTRL_IDs[TCC_INST_NUM+TC_INST_NUM];
-
-#define NOT_ON_PWM NOT_ON_TIMER
-
 #else
 // Definitions for TC channels
 typedef enum _ETCChannel
@ -210,48 +109,7 @@ typedef enum _ETCChannel
  TC4_CH1  = (4<<8)|(1),
  TC5_CH0  = (5<<8)|(0),
  TC5_CH1  = (5<<8)|(1),
-  #if defined (__SAMD21J18A__) 
-    TC6_CH0  = (6<<8)|(0),
-    TC6_CH1  = (6<<8)|(1),
-    TC7_CH0  = (7<<8)|(0),
-    TC7_CH1  = (7<<8)|(1),
-  #endif // __SAMD21J18A__
 } ETCChannel ;
-
-// Definitions for PWM channels
-typedef enum _EPWMChannel
-{
-  NOT_ON_PWM=-1,
-  PWM0_CH0=TCC0_CH0,
-  PWM0_CH1=TCC0_CH1,
-  PWM0_CH2=TCC0_CH2,
-  PWM0_CH3=TCC0_CH3,
-  PWM0_CH4=TCC0_CH4,
-  PWM0_CH5=TCC0_CH5,
-  PWM0_CH6=TCC0_CH6,
-  PWM0_CH7=TCC0_CH7,
-  PWM1_CH0=TCC1_CH0,
-  PWM1_CH1=TCC1_CH1,
-  PWM1_CH2=TCC1_CH2,
-  PWM1_CH3=TCC1_CH3,
-  PWM2_CH0=TCC2_CH0,
-  PWM2_CH1=TCC2_CH1,
-  PWM2_CH2=TCC2_CH2,
-  PWM2_CH3=TCC2_CH3,
-  PWM3_CH0=TC3_CH0,
-  PWM3_CH1=TC3_CH1,
-  PWM4_CH0=TC4_CH0,
-  PWM4_CH1=TC4_CH1,
-  PWM5_CH0=TC5_CH0,
-  PWM5_CH1=TC5_CH1,
-#if defined(__SAMD21J18A__)
-  PWM6_CH0=TC6_CH0,
-  PWM6_CH1=TC6_CH1,
-  PWM7_CH0=TC7_CH0,
-  PWM7_CH1=TC7_CH1,
-#endif // __SAMD21J18A__
-} EPWMChannel ;
-
 #endif

 extern const void* g_apTCInstances[TCC_INST_NUM+TC_INST_NUM] ;
@ -260,13 +118,74 @@ extern const void* g_apTCInstances[TCC_INST_NUM+TC_INST_NUM] ;
 #define GetTCChannelNumber( x ) ( (x) & 0xff )
 #define GetTC( x ) ( g_apTCInstances[(x) >> 8] )

+
+#if defined(__SAMD51__)
+
+  typedef enum _EPWMChannel
+  {
+    NOT_ON_PWM=-1,
+    PWM0_CH0=TCC0_CH0,
+    PWM0_CH1=TCC0_CH1,
+    PWM0_CH2=TCC0_CH2,
+    PWM0_CH3=TCC0_CH3,
+    PWM0_CH4=TCC0_CH4,
+    PWM0_CH5=TCC0_CH5,
+    PWM0_CH6=TCC0_CH6,
+    PWM0_CH7=TCC0_CH7,
+    PWM1_CH0=TCC1_CH0,
+    PWM1_CH1=TCC1_CH1,
+    PWM1_CH2=TCC1_CH2,
+    PWM1_CH3=TCC1_CH3,
+    PWM1_CH4=TCC1_CH4,
+    PWM1_CH5=TCC1_CH5,
+    PWM1_CH6=TCC1_CH6,
+    PWM1_CH7=TCC1_CH7,
+  } EPWMChannel ;
+
+#else //end __SAMD51J19A__
+  // Definitions for PWM channels
+  typedef enum _EPWMChannel
+  {
+    NOT_ON_PWM=-1,
+    PWM0_CH0=TCC0_CH0,
+    PWM0_CH1=TCC0_CH1,
+    PWM0_CH2=TCC0_CH2,
+    PWM0_CH3=TCC0_CH3,
+    PWM0_CH4=TCC0_CH4,
+    PWM0_CH5=TCC0_CH5,
+    PWM0_CH6=TCC0_CH6,
+    PWM0_CH7=TCC0_CH7,
+    PWM1_CH0=TCC1_CH0,
+    PWM1_CH1=TCC1_CH1,
+    PWM1_CH2=TCC1_CH2,
+    PWM1_CH3=TCC1_CH3,
+    PWM2_CH0=TCC2_CH0,
+    PWM2_CH1=TCC2_CH1,
+    PWM2_CH2=TCC2_CH2,
+    PWM2_CH3=TCC2_CH3,
+    PWM3_CH0=TC3_CH0,
+    PWM3_CH1=TC3_CH1,
+    PWM4_CH0=TC4_CH0,
+    PWM4_CH1=TC4_CH1,
+    PWM5_CH0=TC5_CH0,
+    PWM5_CH1=TC5_CH1,
+  #if defined(__SAMD21J18A__)
+    PWM6_CH0=TC6_CH0,
+    PWM6_CH1=TC6_CH1,
+    PWM7_CH0=TC7_CH0,
+    PWM7_CH1=TC7_CH1,
+  #endif // __SAMD21J18A__
+  } EPWMChannel ;
+
+#endif
+
+
 typedef enum _EPortType
 {
  NOT_A_PORT=-1,
  PORTA=0,
  PORTB=1,
  PORTC=2,
-  PORTD=3,
 } EPortType ;

 #define PIN_NOT_A_PIN (UINT_MAX)
@ -336,19 +255,10 @@ typedef enum _EPioType
 #define PIN_ATTR_COMBO         (1UL<<0)
 #define PIN_ATTR_ANALOG        (1UL<<1)
 #define PIN_ATTR_DIGITAL       (1UL<<2)
+#define PIN_ATTR_PWM           (1UL<<3)
 #define PIN_ATTR_TIMER         (1UL<<4)
 #define PIN_ATTR_TIMER_ALT     (1UL<<5)
 #define PIN_ATTR_EXTINT        (1UL<<6)
-#define PIN_ATTR_ANALOG_ALT	   (1UL<<7)
-
-#if defined(__SAMD51__)
-// these correspond to the mux table
-#define PIN_ATTR_PWM_E         (1UL<<3)
-#define PIN_ATTR_PWM_F         (1UL<<8)
-#define PIN_ATTR_PWM_G         (1UL<<9)
-#else
-#define PIN_ATTR_PWM           (1UL<<3)
-#endif

 /* Types used for the table below */
 typedef struct _PinDescription
--- a/cores/arduino/avr/io.h
+++ b/cores/arduino/avr/io.h
@ -25,14 +25,8 @@
 #ifndef _IO_H_
 #define _IO_H_

-#ifdef __SAMD51__
-  #define RAMSTART (HSRAM_ADDR)
-  #define RAMSIZE  (HSRAM_SIZE)
-#else
-  #define RAMSTART (HMCRAMC0_ADDR)
-  #define RAMSIZE  (HMCRAMC0_SIZE)
-#endif
-
+#define RAMSTART (HMCRAMC0_ADDR)
+#define RAMSIZE  (HMCRAMC0_SIZE)
 #define RAMEND   (RAMSTART + RAMSIZE - 1)

 #endif
--- a/cores/arduino/delay.c
+++ b/cores/arduino/delay.c
@ -61,51 +61,19 @@ unsigned long micros( void )
  // a runtime multiplication and shift, saving a few cycles
 }

-#ifdef __SAMD51__
-/*
- * On SAMD51, use the (32bit) cycle count maintained by the DWT unit,
- * and count exact number of cycles elapsed, rather than guessing how
- * many cycles a loop takes, which is dangerous in the presence of
- * cache.  The overhead of the call and internal code is "about" 20
- * cycles.  (at 120MHz, that's about 1/6 us)
- */
-void delayMicroseconds(unsigned int us)
-{
-  uint32_t start, elapsed;
-  uint32_t count;
-
-  if (us == 0)
-    return;
-
-  count = us * (VARIANT_MCK / 1000000) - 20;  // convert us to cycles.
-  start = DWT->CYCCNT;  //CYCCNT is 32bits, takes 37s or so to wrap.
-  while (1) {
-    elapsed = DWT->CYCCNT - start;
-    if (elapsed >= count)
-      return;
-  }
-}
-#endif
-
-
 void delay( unsigned long ms )
 {
-  if (ms == 0)
+  if ( ms == 0 )
  {
-    return;
+    return ;
  }

-  uint32_t start = micros();
+  uint32_t start = _ulTickCount ;

-  while (ms > 0)
+  do
  {
-    yield();
-    while (ms > 0 && (micros() - start) >= 1000)
-    {
-      ms--;
-      start += 1000;
-    }
-  }
+    yield() ;
+  } while ( _ulTickCount - start < ms ) ;
 }

 #include "Reset.h" // for tickReset()
--- a/cores/arduino/delay.h
+++ b/cores/arduino/delay.h
@ -61,9 +61,6 @@ extern void delay( unsigned long dwMs ) ;
 *
 * \param dwUs the number of microseconds to pause (uint32_t)
 */
-#if defined(__SAMD51__)
-extern void delayMicroseconds( unsigned int );
-#else
 static __inline__ void delayMicroseconds( unsigned int ) __attribute__((always_inline, unused)) ;
 static __inline__ void delayMicroseconds( unsigned int usec )
 {
@ -71,6 +68,21 @@ static __inline__ void delayMicroseconds( unsigned int usec )
  {
    return ;
  }
+
+#if defined(__SAMD51__)
+  uint32_t n = usec * (VARIANT_MCK / 1000000) / 12;
+
+  __asm__ __volatile__(
+    "1:              \n"
+    "   sub %0, #1   \n" // substract 1 from %0 (n)
+    "   cmp %0, #0   \n" // compare to 0
+    "   bne 1b       \n" // if result is not 0 jump to 1
+    : "+r" (n)           // '%0' is n variable with RW constraints
+    :                    // no input
+    :                    // no clobber
+  );
+
+#else
  /*
   *  The following loop:
   *
@ -97,10 +109,10 @@ static __inline__ void delayMicroseconds( unsigned int usec )
    :                    // no input
    :                    // no clobber
  );
+#endif
  // https://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html
  // https://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html#Volatile
 }
-#endif

 #ifdef __cplusplus
 }
--- a/cores/arduino/hooks.c
+++ b/cores/arduino/hooks.c
@ -28,7 +28,6 @@
 static void __empty() {
 	// Empty
 }
-
 void yield(void) __attribute__ ((weak, alias("__empty")));

 /**
--- a/cores/arduino/main.cpp
+++ b/cores/arduino/main.cpp
@ -39,10 +39,7 @@ int main( void )
  initVariant();

  delay(1);
-
-#if defined(USE_TINYUSB)
-  Adafruit_TinyUSB_Core_init();
-#elif defined(USBCON)
+#if defined(USBCON)
  USBDevice.init();
  USBDevice.attach();
 #endif
@ -52,21 +49,8 @@ int main( void )
  for (;;)
  {
    loop();
-    yield(); // yield run usb background task
-
    if (serialEventRun) serialEventRun();
  }

  return 0;
 }
-
-#if defined(USE_TINYUSB)
-
-// run TinyUSB background task when yield()
-extern  "C" void yield(void)
-{
-  tud_task();
-  tud_cdc_write_flush();
-}
-
-#endif
--- a/cores/arduino/math_helper.c
+++ b/cores/arduino/math_helper.c
@ -164,19 +164,18 @@ void arm_float_to_q12_20(float *pIn, q31_t * pOut, uint32_t numSamples)
 uint32_t arm_compare_fixed_q15(q15_t *pIn, q15_t * pOut, uint32_t numSamples)
 {
  uint32_t i; 
-  int32_t diff;
-  uint32_t diffCrnt = 0;
+  int32_t diff, diffCrnt = 0;
  uint32_t maxDiff = 0;

  for (i = 0; i < numSamples; i++)
  {
-    diff = pIn[i] - pOut[i];
-    diffCrnt = (uint32_t)( (diff > 0) ? diff : -diff );
+  	diff = pIn[i] - pOut[i];
+  	diffCrnt = (diff > 0) ? diff : -diff;

-    if(diffCrnt > maxDiff)
-    {
-      maxDiff = diffCrnt;
-    }
+	if(diffCrnt > maxDiff)
+	{
+		maxDiff = diffCrnt;
+	}	
  }

  return(maxDiff);
@ -193,19 +192,18 @@ uint32_t arm_compare_fixed_q15(q15_t *pIn, q15_t * pOut, uint32_t numSamples)
 uint32_t arm_compare_fixed_q31(q31_t *pIn, q31_t * pOut, uint32_t numSamples)
 {
  uint32_t i; 
-  int32_t diff;
-  uint32_t diffCrnt = 0;
+  int32_t diff, diffCrnt = 0;
  uint32_t maxDiff = 0;

  for (i = 0; i < numSamples; i++)
  {
-    diff = pIn[i] - pOut[i];
-    diffCrnt = (uint32_t)( (diff > 0) ? diff : -diff );
+  	diff = pIn[i] - pOut[i];
+  	diffCrnt = (diff > 0) ? diff : -diff;

-    if(diffCrnt > maxDiff)
-    {
-      maxDiff = diffCrnt;
-    }
+	if(diffCrnt > maxDiff)
+	{
+		maxDiff = diffCrnt;
+	}
  }

  return(maxDiff);
--- a/cores/arduino/pulse.c
+++ b/cores/arduino/pulse.c
@ -34,36 +34,6 @@ uint32_t pulseIn(uint32_t pin, uint32_t state, uint32_t timeout)
  uint32_t bit = 1 << p.ulPin;
  uint32_t stateMask = state ? bit : 0;

-#if defined(__SAMD51__)
-  /*
-   * The SAMD51 is fast enough to use really obvious code (similar to
-   * what was used to produce pulse_asm.S, but using micros() for timing.
-   * No assembly required, no conversion of loop counts to times (which is
-   * worrisome in the presence of cache.)
-   */
-  const volatile uint32_t *port = &(PORT->Group[p.ulPort].IN.reg);
-  uint32_t usCallStart;  // microseconds at start of call, for timeout.
-  uint32_t usPulseStart; // microseconds at start of measured pulse.
-  usCallStart = usPulseStart = micros();
-  // wait for any previous pulse to end
-  while ((*port & bit) == stateMask) {
-      if (micros() - usCallStart > timeout)
-          return -1;
-  }
-  // wait for the pulse to start
-  while ((*port & bit) != stateMask) {
-      usPulseStart = micros();
-      if (usPulseStart - usCallStart > timeout)
-          return -2;
-  }
-
-  // wait for the pulse to stop
-  while ((*port & bit) == stateMask) {
-      if (micros() - usCallStart > timeout)
-          return -3;
-  }
-  return micros() - usPulseStart;
-#else
  // convert the timeout from microseconds to a number of times through
  // the initial loop; it takes (roughly) 13 clock cycles per iteration.
  uint32_t maxloops = microsecondsToClockCycles(timeout) / 13;
@ -78,6 +48,5 @@ uint32_t pulseIn(uint32_t pin, uint32_t state, uint32_t timeout)
    return clockCyclesToMicroseconds(width * 13 + 16);
  else
    return 0;
-#endif // SAMD51
 }

--- a/cores/arduino/startup.c
+++ b/cores/arduino/startup.c
@ -97,7 +97,7 @@ void SystemInit( void )
  }
  
  /* ----------------------------------------------------------------------------------------------
-   * 3) Put OSCULP32K as source for Generic Clock Generator 0
+   * 3) Put Generic Clock Generator 3 as source for Generic Clock Gen 0 (DFLL48M reference)
   */
  GCLK->GENCTRL[0].reg = GCLK_GENCTRL_SRC(GCLK_GENCTRL_SRC_OSCULP32K) | GCLK_GENCTRL_GENEN;
  
@ -146,7 +146,7 @@ void SystemInit( void )
      /* Wait for synchronization */
    }
  
-  GCLK->GENCTRL[GENERIC_CLOCK_GENERATOR_1M].reg = GCLK_GENCTRL_SRC(GCLK_GENCTRL_SRC_DFLL_Val) | GCLK_GENCTRL_GENEN | GCLK_GENCTRL_DIV(48u);
+  GCLK->GENCTRL[GENERIC_CLOCK_GENERATOR_1M].reg = GCLK_GENCTRL_SRC(GCLK_GENCTRL_SRC_DFLL_Val) | GCLK_GENCTRL_GENEN | GCLK_GENCTRL_DIV(24u);
  
  while ( GCLK->SYNCBUSY.bit.GENCTRL5 ){
    /* Wait for synchronization */
@ -160,8 +160,7 @@ void SystemInit( void )
  //PLL0 is 120MHz
  GCLK->PCHCTRL[OSCCTRL_GCLK_ID_FDPLL0].reg = (1 << GCLK_PCHCTRL_CHEN_Pos) | GCLK_PCHCTRL_GEN(GCLK_PCHCTRL_GEN_GCLK5_Val);
  
-  // This rounds to nearest full-MHz increment; not currently using frac
-  OSCCTRL->Dpll[0].DPLLRATIO.reg = OSCCTRL_DPLLRATIO_LDRFRAC(0x00) | OSCCTRL_DPLLRATIO_LDR((F_CPU - 500000) / 1000000);
+  OSCCTRL->Dpll[0].DPLLRATIO.reg = OSCCTRL_DPLLRATIO_LDRFRAC(0x00) | OSCCTRL_DPLLRATIO_LDR(59); //120 Mhz
  
  while(OSCCTRL->Dpll[0].DPLLSYNCBUSY.bit.DPLLRATIO);
  
@ -175,7 +174,7 @@ void SystemInit( void )
  //PLL1 is 100MHz
  GCLK->PCHCTRL[OSCCTRL_GCLK_ID_FDPLL1].reg = (1 << GCLK_PCHCTRL_CHEN_Pos) | GCLK_PCHCTRL_GEN(GCLK_PCHCTRL_GEN_GCLK5_Val);
  
-  OSCCTRL->Dpll[1].DPLLRATIO.reg = OSCCTRL_DPLLRATIO_LDRFRAC(0x00) | OSCCTRL_DPLLRATIO_LDR(99); //100 Mhz
+  OSCCTRL->Dpll[1].DPLLRATIO.reg = OSCCTRL_DPLLRATIO_LDRFRAC(0x00) | OSCCTRL_DPLLRATIO_LDR(49); //100 Mhz
  
  while(OSCCTRL->Dpll[1].DPLLSYNCBUSY.bit.DPLLRATIO);
  
@ -217,7 +216,7 @@ void SystemInit( void )
  GCLK->GENCTRL[GENERIC_CLOCK_GENERATOR_12M].reg = GCLK_GENCTRL_SRC(GCLK_GENCTRL_SRC_DFLL_Val) |
    GCLK_GENCTRL_IDC |
    GCLK_GENCTRL_DIV(4) |
-    //GCLK_GENCTRL_DIVSEL |
+    GCLK_GENCTRL_DIVSEL |
    //GCLK_GENCTRL_OE |
    GCLK_GENCTRL_GENEN;
  
@ -253,55 +252,7 @@ void SystemInit( void )
  CMCC->CTRL.reg = 1;
  __enable_irq();
 #endif
-
-  /*---------------------------------------------------------------------
-   * Start up the "Debug Watchpoint and Trace" unit, so that we can use
-   * it's 32bit cycle counter for timing.
-   */
-  CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;
-  DWT->CTRL |= DWT_CTRL_CYCCNTENA_Msk;
-
-  /* ----------------------------------------------------------------------------------------------
-   * 5) Load AC factory calibration values
-   */
-
-  uint32_t bias0 = (*((uint32_t *)AC_FUSES_BIAS0_ADDR) & AC_FUSES_BIAS0_Msk) >> AC_FUSES_BIAS0_Pos;
-  AC->CALIB.reg = AC_CALIB_BIAS0(bias0);
-
-  /* ----------------------------------------------------------------------------------------------
-   * 6) Load ADC factory calibration values
-   */
-
-  // ADC0 Bias Calibration
-  uint32_t biascomp = (*((uint32_t *)ADC0_FUSES_BIASCOMP_ADDR) & ADC0_FUSES_BIASCOMP_Msk) >> ADC0_FUSES_BIASCOMP_Pos;
-  uint32_t biasr2r = (*((uint32_t *)ADC0_FUSES_BIASR2R_ADDR) & ADC0_FUSES_BIASR2R_Msk) >> ADC0_FUSES_BIASR2R_Pos;
-  uint32_t biasref = (*((uint32_t *)ADC0_FUSES_BIASREFBUF_ADDR) & ADC0_FUSES_BIASREFBUF_Msk) >> ADC0_FUSES_BIASREFBUF_Pos;
-
-  ADC0->CALIB.reg = ADC_CALIB_BIASREFBUF(biasref)
-                    | ADC_CALIB_BIASR2R(biasr2r)
-                    | ADC_CALIB_BIASCOMP(biascomp);
-
-  // ADC1 Bias Calibration
-  biascomp = (*((uint32_t *)ADC1_FUSES_BIASCOMP_ADDR) & ADC1_FUSES_BIASCOMP_Msk) >> ADC1_FUSES_BIASCOMP_Pos;
-  biasr2r = (*((uint32_t *)ADC1_FUSES_BIASR2R_ADDR) & ADC1_FUSES_BIASR2R_Msk) >> ADC1_FUSES_BIASR2R_Pos;
-  biasref = (*((uint32_t *)ADC1_FUSES_BIASREFBUF_ADDR) & ADC1_FUSES_BIASREFBUF_Msk) >> ADC1_FUSES_BIASREFBUF_Pos;
-
-  ADC1->CALIB.reg = ADC_CALIB_BIASREFBUF(biasref)
-                    | ADC_CALIB_BIASR2R(biasr2r)
-                    | ADC_CALIB_BIASCOMP(biascomp);
-
-  /* ----------------------------------------------------------------------------------------------
-   * 7) Load USB factory calibration values
-   */
-
-  //USB Calibration
-  uint32_t usbtransn = (*((uint32_t *)USB_FUSES_TRANSN_ADDR) & USB_FUSES_TRANSN_Msk) >> USB_FUSES_TRANSN_Pos;
-  uint32_t usbtransp = (*((uint32_t *)USB_FUSES_TRANSP_ADDR) & USB_FUSES_TRANSP_Msk) >> USB_FUSES_TRANSP_Pos;
-  uint32_t usbtrim = (*((uint32_t *)USB_FUSES_TRIM_ADDR) & USB_FUSES_TRIM_Msk) >> USB_FUSES_TRIM_Pos;
-  USB->DEVICE.PADCAL.reg = USB_PADCAL_TRIM(usbtrim)
-                           | USB_PADCAL_TRANSN(usbtransn)
-                           | USB_PADCAL_TRANSP(usbtransp);
-
+  
 //*************** END SAMD51 *************************//
  
 #else
@ -577,3 +528,4 @@ void SystemInit( void )
    NVMCTRL->CTRLB.bit.MANW = 1;
  #endif
 }
+
--- a/cores/arduino/wiring.c
+++ b/cores/arduino/wiring.c
@ -25,7 +25,8 @@ extern "C" {


 #if defined(__SAMD51__)
-uint32_t SystemCoreClock=F_CPU;
+//CHANGE THIS IF YOU CHANGE THE CLOCK SPEED
+uint32_t SystemCoreClock=120000000ul ;
 #else
 /*
 * System Core Clock is at 1MHz (8MHz/8) at Reset.
@ -78,21 +79,19 @@ void init( void )
 //  PM->APBAMASK.reg |= PM_APBAMASK_EIC ;

 #if defined(__SAMD51__)
-  MCLK->APBAMASK.reg |= MCLK_APBAMASK_SERCOM0 | MCLK_APBAMASK_SERCOM1 | MCLK_APBAMASK_TC0 | MCLK_APBAMASK_TC1;
+  MCLK->APBAMASK.reg |= MCLK_APBAMASK_SERCOM0 | MCLK_APBAMASK_SERCOM1;
  
  MCLK->APBBMASK.reg |= MCLK_APBBMASK_SERCOM2 | MCLK_APBBMASK_SERCOM3 | MCLK_APBBMASK_TCC0 | MCLK_APBBMASK_TCC1 | MCLK_APBBMASK_TC3 | MCLK_APBBMASK_TC2;
  
-  MCLK->APBCMASK.reg |= MCLK_APBCMASK_TCC2 | MCLK_APBCMASK_TCC3 | MCLK_APBCMASK_TC4 | MCLK_APBCMASK_TC5;
+  MCLK->APBCMASK.reg |= MCLK_APBCMASK_TCC2 | MCLK_APBCMASK_TC4 | MCLK_APBCMASK_TC5;
  
-  MCLK->APBDMASK.reg |= MCLK_APBDMASK_DAC | MCLK_APBDMASK_SERCOM4 | MCLK_APBDMASK_SERCOM5 | MCLK_APBDMASK_ADC0 | MCLK_APBDMASK_ADC1 | MCLK_APBDMASK_TCC4
-		  | MCLK_APBDMASK_TC6 | MCLK_APBDMASK_TC7 | MCLK_APBDMASK_SERCOM6 | MCLK_APBDMASK_SERCOM7;
-
+  MCLK->APBDMASK.reg |= MCLK_APBDMASK_DAC | MCLK_APBDMASK_SERCOM4 | MCLK_APBDMASK_SERCOM5 | MCLK_APBDMASK_ADC0 | MCLK_APBDMASK_ADC1;
 #else
  // Clock SERCOM for Serial
  PM->APBCMASK.reg |= PM_APBCMASK_SERCOM0 | PM_APBCMASK_SERCOM1 | PM_APBCMASK_SERCOM2 | PM_APBCMASK_SERCOM3 | PM_APBCMASK_SERCOM4 | PM_APBCMASK_SERCOM5 ;

  // Clock TC/TCC for Pulse and Analog
-  PM->APBCMASK.reg |= PM_APBCMASK_TCC0 | PM_APBCMASK_TCC1 | PM_APBCMASK_TCC2 | PM_APBCMASK_TC3 | PM_APBCMASK_TC4 | PM_APBCMASK_TC5 | PM_APBCMASK_TC6 | PM_APBCMASK_TC7;
+  PM->APBCMASK.reg |= PM_APBCMASK_TCC0 | PM_APBCMASK_TCC1 | PM_APBCMASK_TCC2 | PM_APBCMASK_TC3 | PM_APBCMASK_TC4 | PM_APBCMASK_TC5 ;

  // ATSAMR, for example, doesn't have a DAC
  #ifdef PM_APBCMASK_DAC
@ -101,45 +100,35 @@ void init( void )
  #endif
 #endif

-/* 
-  Commented out to leave pins in default tri-state.  This is
-  aimed at avoiding power consumption in DeepSleep.
-  
  // Setup all pins (digital and analog) in INPUT mode (default is nothing)
  for (uint32_t ul = 0 ; ul < NUM_DIGITAL_PINS ; ul++ )
  {
    pinMode( ul, INPUT ) ;
  }
-*/

  // Initialize Analog Controller
  // Setting clock
 #if defined(__SAMD51__)
-  //set to 1/(1/(48000000/32) * 6) = 250000 SPS
 	GCLK->PCHCTRL[ADC0_GCLK_ID].reg = GCLK_PCHCTRL_GEN_GCLK1_Val | (1 << GCLK_PCHCTRL_CHEN_Pos); //use clock generator 1 (48Mhz)
-	GCLK->PCHCTRL[ADC1_GCLK_ID].reg = GCLK_PCHCTRL_GEN_GCLK1_Val | (1 << GCLK_PCHCTRL_CHEN_Pos); //use clock generator 1 (48Mhz)
-	Adc *adcs[] = {ADC0, ADC1};
-		for(int i=0; i<2; i++){
-
-		adcs[i]->CTRLA.bit.PRESCALER = ADC_CTRLA_PRESCALER_DIV32_Val;
-		adcs[i]->CTRLB.bit.RESSEL = ADC_CTRLB_RESSEL_10BIT_Val;
-
-		while( adcs[i]->SYNCBUSY.reg & ADC_SYNCBUSY_CTRLB );  //wait for sync
-
-		adcs[i]->SAMPCTRL.reg = 5;                        // sampling Time Length
-
-		while( adcs[i]->SYNCBUSY.reg & ADC_SYNCBUSY_SAMPCTRL );  //wait for sync
-
-		adcs[i]->INPUTCTRL.reg = ADC_INPUTCTRL_MUXNEG_GND;   // No Negative input (Internal Ground)
-
-		while( adcs[i]->SYNCBUSY.reg & ADC_SYNCBUSY_INPUTCTRL );  //wait for sync
-
-		// Averaging (see datasheet table in AVGCTRL register description)
-		adcs[i]->AVGCTRL.reg = ADC_AVGCTRL_SAMPLENUM_1 |    // 1 sample only (no oversampling nor averaging)
-							ADC_AVGCTRL_ADJRES(0x0ul);   // Adjusting result by 0
-
-		while( adcs[i]->SYNCBUSY.reg & ADC_SYNCBUSY_AVGCTRL );  //wait for sync
-	}
+	
+	ADC0->CTRLA.bit.PRESCALER = ADC_CTRLA_PRESCALER_DIV256_Val;
+	ADC0->CTRLB.bit.RESSEL = ADC_CTRLB_RESSEL_10BIT_Val;
+	
+	while( ADC0->SYNCBUSY.reg & ADC_SYNCBUSY_CTRLB );  //wait for sync
+	
+	ADC0->SAMPCTRL.reg = 0x3f;                        // Set max Sampling Time Length
+	
+	while( ADC0->SYNCBUSY.reg & ADC_SYNCBUSY_SAMPCTRL );  //wait for sync
+	
+	ADC0->INPUTCTRL.reg = ADC_INPUTCTRL_MUXNEG_GND;   // No Negative input (Internal Ground)
+	
+	while( ADC0->SYNCBUSY.reg & ADC_SYNCBUSY_INPUTCTRL );  //wait for sync
+	
+	// Averaging (see datasheet table in AVGCTRL register description)
+	ADC0->AVGCTRL.reg = ADC_AVGCTRL_SAMPLENUM_1 |    // 1 sample only (no oversampling nor averaging)
+						ADC_AVGCTRL_ADJRES(0x0ul);   // Adjusting result by 0
+						
+	while( ADC0->SYNCBUSY.reg & ADC_SYNCBUSY_AVGCTRL );  //wait for sync

 	analogReference( AR_DEFAULT ) ; // Analog Reference is AREF pin (3.3v)
 	
@ -157,8 +146,6 @@ void init( void )
 	DAC->DACCTRL[1].bit.REFRESH = 2;

 #else
-  //set to 1/(1/(48000000/32) * 6) = 250000 SPS
-
  while(GCLK->STATUS.reg & GCLK_STATUS_SYNCBUSY);

  GCLK->CLKCTRL.reg = GCLK_CLKCTRL_ID( GCM_ADC ) | // Generic Clock ADC
@ -167,10 +154,10 @@ void init( void )

  while( ADC->STATUS.bit.SYNCBUSY == 1 );          // Wait for synchronization of registers between the clock domains

-  ADC->CTRLB.reg = ADC_CTRLB_PRESCALER_DIV32 |    // Divide Clock by 32.
+  ADC->CTRLB.reg = ADC_CTRLB_PRESCALER_DIV512 |    // Divide Clock by 512.
                   ADC_CTRLB_RESSEL_10BIT;         // 10 bits resolution as default

-  ADC->SAMPCTRL.reg = 5;                        // Sampling Time Length
+  ADC->SAMPCTRL.reg = 0x3f;                        // Set max Sampling Time Length

  while( ADC->STATUS.bit.SYNCBUSY == 1 );          // Wait for synchronization of registers between the clock domains

--- a/cores/arduino/wiring_analog.c
+++ b/cores/arduino/wiring_analog.c
@ -32,7 +32,7 @@ static int _writeResolution = 12;
 static int _dacResolution = 12;
 #else
 static int _writeResolution = 8;
-//static int _dacResolution = 10;
+static int _dacResolution = 8;
 #endif


@ -77,21 +77,17 @@ void analogReadResolution(int res)

 	if (res > 10) {
 		ADC0->CTRLB.bit.RESSEL = ADC_CTRLB_RESSEL_12BIT_Val;
-		ADC1->CTRLB.bit.RESSEL = ADC_CTRLB_RESSEL_12BIT_Val;
 		_ADCResolution = 12;
 		} else if (res > 8) {
 		ADC0->CTRLB.bit.RESSEL = ADC_CTRLB_RESSEL_10BIT_Val;
-		ADC1->CTRLB.bit.RESSEL = ADC_CTRLB_RESSEL_10BIT_Val;
 		_ADCResolution = 10;
 		} else {
 		ADC0->CTRLB.bit.RESSEL = ADC_CTRLB_RESSEL_8BIT_Val;
-		ADC1->CTRLB.bit.RESSEL = ADC_CTRLB_RESSEL_8BIT_Val;
 		_ADCResolution = 8;
 	}


 	while(ADC0->SYNCBUSY.reg & ADC_SYNCBUSY_CTRLB); //wait for sync
-	while(ADC1->SYNCBUSY.reg & ADC_SYNCBUSY_CTRLB); //wait for sync
 #else

 	if (res > 10) {
@ -135,92 +131,38 @@ void analogReference(eAnalogReference mode)
 {
 #if defined(__SAMD51__)
 	while(ADC0->SYNCBUSY.reg & ADC_SYNCBUSY_REFCTRL); //wait for sync
-	while(ADC1->SYNCBUSY.reg & ADC_SYNCBUSY_REFCTRL); //wait for sync
 	
 	//TODO: fix gains
 	switch (mode)
 	{
-		case AR_INTERNAL1V0:
+		case AR_INTERNAL:
+		case AR_INTERNAL2V23:
 		//ADC0->GAINCORR.reg = ADC_GAINCORR_GAINCORR();      // Gain Factor Selection
-		SUPC->VREF.bit.SEL = SUPC_VREF_SEL_1V0_Val;		// select 1.0V
-		SUPC->VREF.bit.VREFOE = 1;	//	Turn on for use with ADC
-		ADC0->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTREF_Val; // Use SUPC.VREF
-		ADC1->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTREF_Val; // 
-		break;
-		
-		case AR_INTERNAL1V1:
-		//ADC0->GAINCORR.reg = ADC_GAINCORR_GAINCORR();      // Gain Factor Selection
-		SUPC->VREF.bit.SEL = SUPC_VREF_SEL_1V1_Val;		// select 1.1V
-		SUPC->VREF.bit.VREFOE = 1;	//	Turn on for use with ADC
-		ADC0->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTREF_Val; // Use SUPC.VREF
-		ADC1->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTREF_Val; // 
-		break;
-		
-		case AR_INTERNAL1V2:
-		//ADC0->GAINCORR.reg = ADC_GAINCORR_GAINCORR();      // Gain Factor Selection
-		SUPC->VREF.bit.SEL = SUPC_VREF_SEL_1V2_Val;		// select 1V2
-		SUPC->VREF.bit.VREFOE = 1;	//	Turn on for use with ADC
-		ADC0->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTREF_Val; // Use SUPC.VREF
-		ADC1->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTREF_Val; // 
+		ADC0->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTVCC0_Val; // 1/1.48 VDDANA = 1/1.48* 3V3 = 2.2297
 		break;

-		case AR_INTERNAL1V25:
-		//ADC0->GAINCORR.reg = ADC_GAINCORR_GAINCORR();      // Gain Factor Selection
-		SUPC->VREF.bit.SEL = SUPC_VREF_SEL_1V25_Val;		// select 1.25V
-		SUPC->VREF.bit.VREFOE = 1;	//	Turn on for use with ADC
-		ADC0->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTREF_Val; // Use SUPC.VREF
-		ADC1->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTREF_Val; // 
-		break;
-		
-		case AR_INTERNAL2V0:
-		//ADC0->GAINCORR.reg = ADC_GAINCORR_GAINCORR();      // Gain Factor Selection
-		SUPC->VREF.bit.SEL = SUPC_VREF_SEL_2V0_Val;		// select 2.0V
-		SUPC->VREF.bit.VREFOE = 1;	//	Turn on for use with ADC
-		ADC0->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTREF_Val; // Use SUPC.VREF
-		ADC1->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTREF_Val; // 
-		break;
-		
-		case AR_INTERNAL2V2:
-		//ADC0->GAINCORR.reg = ADC_GAINCORR_GAINCORR();      // Gain Factor Selection
-		SUPC->VREF.bit.SEL = SUPC_VREF_SEL_2V2_Val;		// select 2.2V
-		SUPC->VREF.bit.VREFOE = 1;	//	Turn on for use with ADC
-		ADC0->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTREF_Val; // Use SUPC.VREF
-		ADC1->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTREF_Val; // 
-		break;
-		
-		case AR_INTERNAL2V4:
-		//ADC0->GAINCORR.reg = ADC_GAINCORR_GAINCORR();      // Gain Factor Selection
-		SUPC->VREF.bit.SEL = SUPC_VREF_SEL_2V4_Val;		// select 2.4V
-		SUPC->VREF.bit.VREFOE = 1;	//	Turn on for use with ADC
-		ADC0->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTREF_Val; // Use SUPC.VREF
-		ADC1->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTREF_Val; // 
-		break;
-		
-		case AR_INTERNAL2V5:
-		//ADC0->GAINCORR.reg = ADC_GAINCORR_GAINCORR();      // Gain Factor Selection
-		SUPC->VREF.bit.SEL = SUPC_VREF_SEL_2V5_Val;		// select 2.5V
-		SUPC->VREF.bit.VREFOE = 1;	//	Turn on for use with ADC
-		ADC0->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTREF_Val; // Use SUPC.VREF
-		ADC1->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTREF_Val; // 
-		break;
-		
 		case AR_EXTERNAL:
 		//ADC0->INPUTCTRL.bit.GAIN = ADC_INPUTCTRL_GAIN_1X_Val;      // Gain Factor Selection
-		ADC0->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_AREFA_Val;	// AREF is jumpered to VCC, so 3.3V
-		ADC1->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_AREFA_Val;
+		ADC0->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_AREFA_Val;
 		break;

-		case AR_INTERNAL1V65:
-		//ADC0->INPUTCTRL.bit.GAIN = ADC_INPUTCTRL_GAIN_DIV2_Val;
-		ADC0->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTVCC0_Val; // 1/2 VDDANA = 1.65
-		ADC1->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTVCC0_Val; // 
+/*		Don't think this works on SAMD51
+		case AR_INTERNAL1V0:
+		//ADC0->INPUTCTRL.bit.GAIN = ADC_INPUTCTRL_GAIN_1X_Val;      // Gain Factor Selection
+		ADC0->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INT1V_Val;   // 1.0V voltage reference
 		break;
-		
+*/
+
+		case AR_INTERNAL1V65:
+		//ADC0->INPUTCTRL.bit.GAIN = ADC_INPUTCTRL_GAIN_1X_Val;      // Gain Factor Selection
+		ADC0->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTVCC1_Val; // 1/2 VDDANA = 0.5* 3V3 = 1.65V
+		break;
+
 		case AR_DEFAULT:
 		default:
 		//ADC0->INPUTCTRL.bit.GAIN = ADC_INPUTCTRL_GAIN_DIV2_Val;
-		ADC0->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTVCC1_Val; // VDDANA = 3V3
-		ADC1->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTVCC1_Val; // 
+		ADC0->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTVCC1_Val; // 1/2 VDDANA = 0.5* 3V3 = 1.65V
+		
 		break;
 	}
 	
@ -228,6 +170,7 @@ void analogReference(eAnalogReference mode)
  syncADC();
  switch (mode)
  {
+    case AR_INTERNAL:
    case AR_INTERNAL2V23:
      ADC->INPUTCTRL.bit.GAIN = ADC_INPUTCTRL_GAIN_1X_Val;      // Gain Factor Selection
      ADC->REFCTRL.bit.REFSEL = ADC_REFCTRL_REFSEL_INTVCC0_Val; // 1/1.48 VDDANA = 1/1.48* 3V3 = 2.2297
@ -280,8 +223,8 @@ uint32_t analogRead(uint32_t pin)
 #ifdef DAC

 	#if defined(__SAMD51__)
-	  if (pin == PIN_DAC0 || pin == PIN_DAC1) { // Disable DAC, if analogWrite(A0,dval) used previously the DAC is enabled
-		uint8_t channel = (pin == PIN_DAC0 ? 0 : 1);
+	  if (pin == A0 || pin == A1) { // Disable DAC, if analogWrite(A0,dval) used previously the DAC is enabled
+		uint8_t channel = (pin == PIN_A0 ? 0 : 1);
 		
 		if(dacEnabled[channel]){
 			dacEnabled[channel] = false;
@ -298,7 +241,7 @@ uint32_t analogRead(uint32_t pin)
 		
 		while (DAC->SYNCBUSY.bit.ENABLE);
 	#else
-	  if (pin == PIN_DAC0) { // Disable DAC, if analogWrite(A0,dval) used previously the DAC is enabled
+	  if (pin == A0) { // Disable DAC, if analogWrite(A0,dval) used previously the DAC is enabled
 	    syncDAC();
 		
 		DAC->CTRLA.bit.ENABLE = 0x00; // Disable DAC
@ -310,13 +253,8 @@ uint32_t analogRead(uint32_t pin)
 #endif

 #if defined(__SAMD51__)
-  Adc *adc;
-  if(g_APinDescription[pin].ulPinAttribute & PIN_ATTR_ANALOG) adc = ADC0;
-  else if(g_APinDescription[pin].ulPinAttribute & PIN_ATTR_ANALOG_ALT) adc = ADC1;
-  else return 0;
-
-  while( adc->SYNCBUSY.reg & ADC_SYNCBUSY_INPUTCTRL ); //wait for sync
-  adc->INPUTCTRL.bit.MUXPOS = g_APinDescription[pin].ulADCChannelNumber; // Selection for the positive ADC input
+  while( ADC0->SYNCBUSY.reg & ADC_SYNCBUSY_INPUTCTRL ); //wait for sync
+  ADC0->INPUTCTRL.bit.MUXPOS = g_APinDescription[pin].ulADCChannelNumber; // Selection for the positive ADC input
  
  // Control A
  /*
@ -330,27 +268,27 @@ uint32_t analogRead(uint32_t pin)
   * Before enabling the ADC, the asynchronous clock source must be selected and enabled, and the ADC reference must be
   * configured. The first conversion after the reference is changed must not be used.
   */
-  while( adc->SYNCBUSY.reg & ADC_SYNCBUSY_ENABLE ); //wait for sync
-  adc->CTRLA.bit.ENABLE = 0x01;             // Enable ADC
+  while( ADC0->SYNCBUSY.reg & ADC_SYNCBUSY_ENABLE ); //wait for sync
+  ADC0->CTRLA.bit.ENABLE = 0x01;             // Enable ADC

  // Start conversion
-  while( adc->SYNCBUSY.reg & ADC_SYNCBUSY_ENABLE ); //wait for sync
+  while( ADC0->SYNCBUSY.reg & ADC_SYNCBUSY_ENABLE ); //wait for sync
  
-  adc->SWTRIG.bit.START = 1;
+  ADC0->SWTRIG.bit.START = 1;

  // Clear the Data Ready flag
-  adc->INTFLAG.reg = ADC_INTFLAG_RESRDY;
+  ADC0->INTFLAG.reg = ADC_INTFLAG_RESRDY;

  // Start conversion again, since The first conversion after the reference is changed must not be used.
-  adc->SWTRIG.bit.START = 1;
+  ADC0->SWTRIG.bit.START = 1;

  // Store the value
-  while (adc->INTFLAG.bit.RESRDY == 0);   // Waiting for conversion to complete
-  valueRead = adc->RESULT.reg;
+  while (ADC0->INTFLAG.bit.RESRDY == 0);   // Waiting for conversion to complete
+  valueRead = ADC0->RESULT.reg;

-  while( adc->SYNCBUSY.reg & ADC_SYNCBUSY_ENABLE ); //wait for sync
-  adc->CTRLA.bit.ENABLE = 0x00;             // Disable ADC
-  while( adc->SYNCBUSY.reg & ADC_SYNCBUSY_ENABLE ); //wait for sync
+  while( ADC0->SYNCBUSY.reg & ADC_SYNCBUSY_ENABLE ); //wait for sync
+  ADC0->CTRLA.bit.ENABLE = 0x00;             // Disable ADC
+  while( ADC0->SYNCBUSY.reg & ADC_SYNCBUSY_ENABLE ); //wait for sync
  
 #else
  syncADC();
@ -406,271 +344,273 @@ void analogWrite(uint32_t pin, uint32_t value)

 // ATSAMR, for example, doesn't have a DAC
 #ifdef DAC
+
 	  if ((attr & PIN_ATTR_ANALOG) == PIN_ATTR_ANALOG)
 	  {
 	    // DAC handling code
-#if defined(__SAMD51__)
-		if (pin == PIN_DAC0 || pin == PIN_DAC1) { // 2 DACs on A0 (PA02) and A1 (PA05)
-#else
-	    if (pin == PIN_DAC0) { // Only 1 DAC on A0 (PA02)
-#endif
+	#if defined(__SAMD51__)
+		if (pin != PIN_A0 && pin != PIN_A1) { // 2 DACs on A0 (PA02) and A1 (PA05)
+	#else
+	    if (pin != PIN_A0) { // Only 1 DAC on A0 (PA02)
+	#endif	
+	      return;
+	    }

-#if defined(__SAMD51__)
+    value = mapResolution(value, _writeResolution, _dacResolution);

-	    value = mapResolution(value, _writeResolution, _dacResolution);
+	#if defined(__SAMD51__)
+		uint8_t channel = (pin == PIN_A0 ? 0 : 1);

+		pinPeripheral(pin, PIO_ANALOG);
+		
+		if(!dacEnabled[channel]){
+			dacEnabled[channel] = true;
+			
+			while (DAC->SYNCBUSY.bit.ENABLE || DAC->SYNCBUSY.bit.SWRST);
+			DAC->CTRLA.bit.ENABLE = 0;     // disable DAC
+			
+			while (DAC->SYNCBUSY.bit.ENABLE || DAC->SYNCBUSY.bit.SWRST);
+			DAC->DACCTRL[channel].bit.ENABLE = 1;
+		
+			while (DAC->SYNCBUSY.bit.ENABLE || DAC->SYNCBUSY.bit.SWRST);
+			DAC->CTRLA.bit.ENABLE = 1;     // enable DAC

-			uint8_t channel = (pin == PIN_DAC0 ? 0 : 1);
+	        if(channel == 0){

-			pinPeripheral(pin, PIO_ANALOG);
+	            while ( !DAC->STATUS.bit.READY0 );

-			if(!dacEnabled[channel]){
-				dacEnabled[channel] = true;
+	            while (DAC->SYNCBUSY.bit.DATA0);
+	            DAC->DATA[0].reg = value;
+	        }
+	        else if(channel == 1){
+	            while ( !DAC->STATUS.bit.READY1 );

-				while (DAC->SYNCBUSY.bit.ENABLE || DAC->SYNCBUSY.bit.SWRST);
-				DAC->CTRLA.bit.ENABLE = 0;     // disable DAC
+	            while (DAC->SYNCBUSY.bit.DATA1);
+	            DAC->DATA[1].reg = value;
+	        }

-				while (DAC->SYNCBUSY.bit.ENABLE || DAC->SYNCBUSY.bit.SWRST);
-				DAC->DACCTRL[channel].bit.ENABLE = 1;
+            delayMicroseconds(10000);
+		}
+		
+		//ERROR!
+		while(!DAC->DACCTRL[channel].bit.ENABLE);
+		
+		if(channel == 0){
+			
+			while ( !DAC->STATUS.bit.READY0 );
+			
+			while (DAC->SYNCBUSY.bit.DATA0);
+			DAC->DATA[0].reg = value;  // DAC on 10 bits.
+		}
+		else if(channel == 1){
+			while ( !DAC->STATUS.bit.READY1 );
+			
+			while (DAC->SYNCBUSY.bit.DATA1);
+			DAC->DATA[1].reg = value;  // DAC on 10 bits.
+		}
+			

-				while (DAC->SYNCBUSY.bit.ENABLE || DAC->SYNCBUSY.bit.SWRST);
-				DAC->CTRLA.bit.ENABLE = 1;     // enable DAC
-
-				if(channel == 0){
-
-					while ( !DAC->STATUS.bit.READY0 );
-
-					while (DAC->SYNCBUSY.bit.DATA0);
-					DAC->DATA[0].reg = value;
-				}
-				else if(channel == 1){
-					while ( !DAC->STATUS.bit.READY1 );
-
-					while (DAC->SYNCBUSY.bit.DATA1);
-					DAC->DATA[1].reg = value;
-				}
-
-				delayMicroseconds(10000);
-			}
-
-			//ERROR!
-			while(!DAC->DACCTRL[channel].bit.ENABLE);
-
-			if(channel == 0){
-
-				while ( !DAC->STATUS.bit.READY0 );
-
-				while (DAC->SYNCBUSY.bit.DATA0);
-				DAC->DATA[0].reg = value;  // DAC on 10 bits.
-			}
-			else if(channel == 1){
-				while ( !DAC->STATUS.bit.READY1 );
-
-				while (DAC->SYNCBUSY.bit.DATA1);
-				DAC->DATA[1].reg = value;  // DAC on 10 bits.
-			}
-
-
-#else
-			syncDAC();
-			DAC->DATA.reg = value & 0x3FF;  // DAC on 10 bits.
-			syncDAC();
-			DAC->CTRLA.bit.ENABLE = 0x01;     // Enable DAC
-			syncDAC();
-#endif // __SAMD51__
-				return;
+	#else
+	    value = mapResolution(value, _dacResolution, 10);
+		syncDAC();
+	    DAC->DATA.reg = value & 0x3FF;  // DAC on 10 bits.
+	    syncDAC();
+	    DAC->CTRLA.bit.ENABLE = 0x01;     // Enable DAC
+	    syncDAC();
+	#endif
+	    return;
 	  }
-	}
-#endif // DAC
-
-#if defined(__SAMD51__)
-	if(attr & (PIN_ATTR_PWM_E|PIN_ATTR_PWM_F|PIN_ATTR_PWM_G)){
-
-		uint32_t tcNum = GetTCNumber(pinDesc.ulPWMChannel);
-		uint8_t tcChannel = GetTCChannelNumber(pinDesc.ulPWMChannel);
-		static bool tcEnabled[TCC_INST_NUM+TC_INST_NUM];
-
-		if(attr & PIN_ATTR_PWM_E)
-			pinPeripheral(pin, PIO_TIMER);
-		else if(attr & PIN_ATTR_PWM_F)
-			pinPeripheral(pin, PIO_TIMER_ALT);
-		else if(attr & PIN_ATTR_PWM_G)
-			pinPeripheral(pin, PIO_TCC_PDEC);
-
-		if (!tcEnabled[tcNum]) {
-		  tcEnabled[tcNum] = true;
-	      GCLK->PCHCTRL[GCLK_CLKCTRL_IDs[tcNum]].reg = GCLK_PCHCTRL_GEN_GCLK0_Val | (1 << GCLK_PCHCTRL_CHEN_Pos); //use clock generator 0
-
-	      // Set PORT
-	      if (tcNum >= TCC_INST_NUM) {
-				// -- Configure TC
-				Tc* TCx = (Tc*) GetTC(pinDesc.ulPWMChannel);
-
-				//reset
-				TCx->COUNT8.CTRLA.bit.SWRST = 1;
-				while (TCx->COUNT8.SYNCBUSY.bit.SWRST);
-
-				// Disable TCx
-				TCx->COUNT8.CTRLA.bit.ENABLE = 0;
-				while (TCx->COUNT8.SYNCBUSY.bit.ENABLE);
-				// Set Timer counter Mode to 8 bits, normal PWM, prescaler 1/256
-				TCx->COUNT8.CTRLA.reg = TC_CTRLA_MODE_COUNT8 | TC_CTRLA_PRESCALER_DIV256;
-				TCx->COUNT8.WAVE.reg = TC_WAVE_WAVEGEN_NPWM;
-
-				while (TCx->COUNT8.SYNCBUSY.bit.CC0);
-				// Set the initial value
-				TCx->COUNT8.CC[tcChannel].reg = (uint8_t) value;
-				while (TCx->COUNT8.SYNCBUSY.bit.CC0);
-				// Set PER to maximum counter value (resolution : 0xFF)
-				TCx->COUNT8.PER.reg = 0xFF;
-				while (TCx->COUNT8.SYNCBUSY.bit.PER);
-				// Enable TCx
-				TCx->COUNT8.CTRLA.bit.ENABLE = 1;
-				while (TCx->COUNT8.SYNCBUSY.bit.ENABLE);
-			} else {
-				// -- Configure TCC
-				Tcc* TCCx = (Tcc*) GetTC(pinDesc.ulPWMChannel);
-
-				TCCx->CTRLA.bit.SWRST = 1;
-				while (TCCx->SYNCBUSY.bit.SWRST);
-
-				// Disable TCCx
-				TCCx->CTRLA.bit.ENABLE = 0;
-				while (TCCx->SYNCBUSY.bit.ENABLE);
-				// Set prescaler to 1/256
-				TCCx->CTRLA.reg = TCC_CTRLA_PRESCALER_DIV256 | TCC_CTRLA_PRESCSYNC_GCLK;
-
-				// Set TCx as normal PWM
-				TCCx->WAVE.reg = TCC_WAVE_WAVEGEN_NPWM;
-				while ( TCCx->SYNCBUSY.bit.WAVE );
-
-				while (TCCx->SYNCBUSY.bit.CC0 || TCCx->SYNCBUSY.bit.CC1);
-				// Set the initial value
-				TCCx->CC[tcChannel].reg = (uint32_t) value;
-				while (TCCx->SYNCBUSY.bit.CC0 || TCCx->SYNCBUSY.bit.CC1);
-				// Set PER to maximum counter value (resolution : 0xFF)
-				TCCx->PER.reg = 0xFF;
-				while (TCCx->SYNCBUSY.bit.PER);
-				// Enable TCCx
-				TCCx->CTRLA.bit.ENABLE = 1;
-				while (TCCx->SYNCBUSY.bit.ENABLE);
-			}
-		}
-		else {
-			if (tcNum >= TCC_INST_NUM) {
-				Tc* TCx = (Tc*) GetTC(pinDesc.ulPWMChannel);
-				TCx->COUNT8.CC[tcChannel].reg = (uint8_t) value;
-				while (TCx->COUNT8.SYNCBUSY.bit.CC0 || TCx->COUNT8.SYNCBUSY.bit.CC1);
-				} else {
-				Tcc* TCCx = (Tcc*) GetTC(pinDesc.ulPWMChannel);
-				while (TCCx->SYNCBUSY.bit.CTRLB);
-				while (TCCx->SYNCBUSY.bit.CC0 || TCCx->SYNCBUSY.bit.CC1);
-				TCCx->CCBUF[tcChannel].reg = (uint32_t) value;
-				while (TCCx->SYNCBUSY.bit.CC0 || TCCx->SYNCBUSY.bit.CC1);
-				TCCx->CTRLBCLR.bit.LUPD = 1;
-				while (TCCx->SYNCBUSY.bit.CTRLB);
-				}
-		}
-
-		return;
-	}
-	  
-#else
+#endif

  if ((attr & PIN_ATTR_PWM) == PIN_ATTR_PWM)
-	  {
-	  value = mapResolution(value, _writeResolution, 16);
+  {
+#ifndef __SAMD51__
+    value = mapResolution(value, _writeResolution, 16);
+	#endif

-	  uint32_t tcNum = GetTCNumber(pinDesc.ulPWMChannel);
-	  uint8_t tcChannel = GetTCChannelNumber(pinDesc.ulPWMChannel);
-	  static bool tcEnabled[TCC_INST_NUM+TC_INST_NUM];
+    uint32_t tcNum = GetTCNumber(pinDesc.ulPWMChannel);
+    uint8_t tcChannel = GetTCChannelNumber(pinDesc.ulPWMChannel);
+    static bool tcEnabled[TCC_INST_NUM+TC_INST_NUM];

-	    if (attr & PIN_ATTR_TIMER) {
-#if !(ARDUINO_SAMD_VARIANT_COMPLIANCE >= 10603)
-	      // Compatibility for cores based on SAMD core <=1.6.2
-	      if (pinDesc.ulPinType == PIO_TIMER_ALT) {
-	        pinPeripheral(pin, PIO_TIMER_ALT);
-	      } else
+    if (attr & PIN_ATTR_TIMER) {
+      #if !(ARDUINO_SAMD_VARIANT_COMPLIANCE >= 10603)
+      // Compatibility for cores based on SAMD core <=1.6.2
+      if (pinDesc.ulPinType == PIO_TIMER_ALT) {
+        pinPeripheral(pin, PIO_TIMER_ALT);
+      } else
+      #endif
+      {
+
+#if defined(__SAMD51__)
+          //on SAMD51 we are only using TCC for timers
+          pinPeripheral(pin, PIO_TCC_PDEC);
+#else
+        pinPeripheral(pin, PIO_TIMER);
 #endif
-	      {
-	        pinPeripheral(pin, PIO_TIMER);
-	      }
-	    } else if ((attr & PIN_ATTR_TIMER_ALT) == PIN_ATTR_TIMER_ALT){
-	        //this is on an alt timer
-	        pinPeripheral(pin, PIO_TIMER_ALT);
-	    }
-	    else{
-	        return;
-	    }
+      }
+    } else if ((attr & PIN_ATTR_TIMER_ALT) == PIN_ATTR_TIMER_ALT){
+        //this is on an alt timer
+        pinPeripheral(pin, PIO_TIMER_ALT);
+    }
+    else{
+        return;
+    }

-	    if (!tcEnabled[tcNum]) {
-	      tcEnabled[tcNum] = true;
-		  uint16_t GCLK_CLKCTRL_IDs[] = {
-			GCLK_CLKCTRL_ID(GCM_TCC0_TCC1), // TCC0
-			GCLK_CLKCTRL_ID(GCM_TCC0_TCC1), // TCC1
-			GCLK_CLKCTRL_ID(GCM_TCC2_TC3),  // TCC2
-			GCLK_CLKCTRL_ID(GCM_TCC2_TC3),  // TC3
-			GCLK_CLKCTRL_ID(GCM_TC4_TC5),   // TC4
-			GCLK_CLKCTRL_ID(GCM_TC4_TC5),   // TC5
-			GCLK_CLKCTRL_ID(GCM_TC6_TC7),   // TC6
-			GCLK_CLKCTRL_ID(GCM_TC6_TC7),   // TC7
-		  };
-		  GCLK->CLKCTRL.reg = (uint16_t) (GCLK_CLKCTRL_CLKEN | GCLK_CLKCTRL_GEN_GCLK0 | GCLK_CLKCTRL_IDs[tcNum]);
-		  while (GCLK->STATUS.bit.SYNCBUSY == 1);
+    if (!tcEnabled[tcNum]) {
+      tcEnabled[tcNum] = true;

-		  // Set PORT
-		  if (tcNum >= TCC_INST_NUM) {
+#if defined(__SAMD51__)
+	uint32_t GCLK_CLKCTRL_IDs[] = {
+		TCC0_GCLK_ID,
+		TCC1_GCLK_ID,
+		TCC2_GCLK_ID,
+	#if defined(TCC3)
+		TCC3_GCLK_ID,
+		TCC4_GCLK_ID,
+		TC5_GCLK_ID,
+	#endif
+	};
+	
+	 GCLK->PCHCTRL[GCLK_CLKCTRL_IDs[tcNum]].reg = GCLK_PCHCTRL_GEN_GCLK0_Val | (1 << GCLK_PCHCTRL_CHEN_Pos); //use clock generator 0
+	  
+	// Set PORT
+	if (tcNum >= TCC_INST_NUM) {
 			// -- Configure TC
 			Tc* TCx = (Tc*) GetTC(pinDesc.ulPWMChannel);
+			
+			//reset
+			TCx->COUNT8.CTRLA.bit.SWRST = 1;
+			while (TCx->COUNT8.SYNCBUSY.bit.SWRST);
+			
 			// Disable TCx
-			TCx->COUNT16.CTRLA.bit.ENABLE = 0;
-			syncTC_16(TCx);
-			// Set Timer counter Mode to 16 bits, normal PWM
-			TCx->COUNT16.CTRLA.reg |= TC_CTRLA_MODE_COUNT16 | TC_CTRLA_WAVEGEN_NPWM;
-			syncTC_16(TCx);
+			TCx->COUNT8.CTRLA.bit.ENABLE = 0;
+			while (TCx->COUNT8.SYNCBUSY.bit.ENABLE);
+			// Set Timer counter Mode to 8 bits, normal PWM, prescaler 1/256
+			TCx->COUNT8.CTRLA.reg = TC_CTRLA_MODE_COUNT8 | TC_CTRLA_PRESCALER_DIV256;
+			TCx->COUNT8.WAVE.reg = TC_WAVE_WAVEGEN_NPWM;
+
+			while (TCx->COUNT8.SYNCBUSY.bit.CC0);
 			// Set the initial value
-			TCx->COUNT16.CC[tcChannel].reg = (uint32_t) value;
-			syncTC_16(TCx);
+			TCx->COUNT8.CC[tcChannel].reg = (uint8_t) value;
+			while (TCx->COUNT8.SYNCBUSY.bit.CC0);
+			// Set PER to maximum counter value (resolution : 0xFF)
+			TCx->COUNT8.PER.reg = 0xFF;
+			while (TCx->COUNT8.SYNCBUSY.bit.PER);
 			// Enable TCx
-			TCx->COUNT16.CTRLA.bit.ENABLE = 1;
-			syncTC_16(TCx);
-		  } else {
+			TCx->COUNT8.CTRLA.bit.ENABLE = 1;
+			while (TCx->COUNT8.SYNCBUSY.bit.ENABLE);
+		} else {
 			// -- Configure TCC
 			Tcc* TCCx = (Tcc*) GetTC(pinDesc.ulPWMChannel);
+			
+			TCCx->CTRLA.bit.SWRST = 1;
+			while (TCCx->SYNCBUSY.bit.SWRST);
+			
 			// Disable TCCx
 			TCCx->CTRLA.bit.ENABLE = 0;
-			syncTCC(TCCx);
-			// Set TCCx as normal PWM
-			TCCx->WAVE.reg |= TCC_WAVE_WAVEGEN_NPWM;
-			syncTCC(TCCx);
+			while (TCCx->SYNCBUSY.bit.ENABLE);
+			// Set prescaler to 1/256
+			TCCx->CTRLA.reg = TCC_CTRLA_PRESCALER_DIV256 | TCC_CTRLA_PRESCSYNC_GCLK;
+			
+			// Set TCx as normal PWM
+			TCCx->WAVE.reg = TCC_WAVE_WAVEGEN_NPWM;
+			while ( TCCx->SYNCBUSY.bit.WAVE );
+			
+			while (TCCx->SYNCBUSY.bit.CC0 || TCCx->SYNCBUSY.bit.CC1);
 			// Set the initial value
 			TCCx->CC[tcChannel].reg = (uint32_t) value;
-			syncTCC(TCCx);
-			// Set PER to maximum counter value (resolution : 0xFFFF)
-			TCCx->PER.reg = 0xFFFF;
-			syncTCC(TCCx);
+			while (TCCx->SYNCBUSY.bit.CC0 || TCCx->SYNCBUSY.bit.CC1);
+			// Set PER to maximum counter value (resolution : 0xFF)
+			TCCx->PER.reg = 0xFF;
+			while (TCCx->SYNCBUSY.bit.PER);
 			// Enable TCCx
 			TCCx->CTRLA.bit.ENABLE = 1;
-			syncTCC(TCCx);
-		  }
+			while (TCCx->SYNCBUSY.bit.ENABLE);
+	}
+	} else {
+	if (tcNum >= TCC_INST_NUM) {
+		Tc* TCx = (Tc*) GetTC(pinDesc.ulPWMChannel);
+		TCx->COUNT8.CC[tcChannel].reg = (uint8_t) value;
+		while (TCx->COUNT8.SYNCBUSY.bit.CC0 || TCx->COUNT8.SYNCBUSY.bit.CC1);
 		} else {
-		  if (tcNum >= TCC_INST_NUM) {
-			Tc* TCx = (Tc*) GetTC(pinDesc.ulPWMChannel);
-			TCx->COUNT16.CC[tcChannel].reg = (uint32_t) value;
-			syncTC_16(TCx);
-		  } else {
-			Tcc* TCCx = (Tcc*) GetTC(pinDesc.ulPWMChannel);
-			TCCx->CTRLBSET.bit.LUPD = 1;
-			syncTCC(TCCx);
-			TCCx->CCB[tcChannel].reg = (uint32_t) value;
-			syncTCC(TCCx);
-			TCCx->CTRLBCLR.bit.LUPD = 1;
-			syncTCC(TCCx);
-		  }
-		}
-	  return;
-  }
+		Tcc* TCCx = (Tcc*) GetTC(pinDesc.ulPWMChannel);
+		while (TCCx->SYNCBUSY.bit.CTRLB);
+		while (TCCx->SYNCBUSY.bit.CC0 || TCCx->SYNCBUSY.bit.CC1);
+		TCCx->CCBUF[tcChannel].reg = (uint32_t) value;
+		while (TCCx->SYNCBUSY.bit.CC0 || TCCx->SYNCBUSY.bit.CC1);
+		TCCx->CTRLBCLR.bit.LUPD = 1;
+		while (TCCx->SYNCBUSY.bit.CTRLB);
+	}
+}
+	  
+#else
+      uint16_t GCLK_CLKCTRL_IDs[] = {
+        GCLK_CLKCTRL_ID(GCM_TCC0_TCC1), // TCC0
+        GCLK_CLKCTRL_ID(GCM_TCC0_TCC1), // TCC1
+        GCLK_CLKCTRL_ID(GCM_TCC2_TC3),  // TCC2
+        GCLK_CLKCTRL_ID(GCM_TCC2_TC3),  // TC3
+        GCLK_CLKCTRL_ID(GCM_TC4_TC5),   // TC4
+        GCLK_CLKCTRL_ID(GCM_TC4_TC5),   // TC5
+        GCLK_CLKCTRL_ID(GCM_TC6_TC7),   // TC6
+        GCLK_CLKCTRL_ID(GCM_TC6_TC7),   // TC7
+      };
+      GCLK->CLKCTRL.reg = (uint16_t) (GCLK_CLKCTRL_CLKEN | GCLK_CLKCTRL_GEN_GCLK0 | GCLK_CLKCTRL_IDs[tcNum]);
+      while (GCLK->STATUS.bit.SYNCBUSY == 1);
+
+      // Set PORT
+      if (tcNum >= TCC_INST_NUM) {
+        // -- Configure TC
+        Tc* TCx = (Tc*) GetTC(pinDesc.ulPWMChannel);
+        // Disable TCx
+        TCx->COUNT16.CTRLA.bit.ENABLE = 0;
+        syncTC_16(TCx);
+        // Set Timer counter Mode to 16 bits, normal PWM
+        TCx->COUNT16.CTRLA.reg |= TC_CTRLA_MODE_COUNT16 | TC_CTRLA_WAVEGEN_NPWM;
+        syncTC_16(TCx);
+        // Set the initial value
+        TCx->COUNT16.CC[tcChannel].reg = (uint32_t) value;
+        syncTC_16(TCx);
+        // Enable TCx
+        TCx->COUNT16.CTRLA.bit.ENABLE = 1;
+        syncTC_16(TCx);
+      } else {
+        // -- Configure TCC
+        Tcc* TCCx = (Tcc*) GetTC(pinDesc.ulPWMChannel);
+        // Disable TCCx
+        TCCx->CTRLA.bit.ENABLE = 0;
+        syncTCC(TCCx);
+        // Set TCCx as normal PWM
+        TCCx->WAVE.reg |= TCC_WAVE_WAVEGEN_NPWM;
+        syncTCC(TCCx);
+        // Set the initial value
+        TCCx->CC[tcChannel].reg = (uint32_t) value;
+        syncTCC(TCCx);
+        // Set PER to maximum counter value (resolution : 0xFFFF)
+        TCCx->PER.reg = 0xFFFF;
+        syncTCC(TCCx);
+        // Enable TCCx
+        TCCx->CTRLA.bit.ENABLE = 1;
+        syncTCC(TCCx);
+      }
+    } else {
+      if (tcNum >= TCC_INST_NUM) {
+        Tc* TCx = (Tc*) GetTC(pinDesc.ulPWMChannel);
+        TCx->COUNT16.CC[tcChannel].reg = (uint32_t) value;
+        syncTC_16(TCx);
+      } else {
+        Tcc* TCCx = (Tcc*) GetTC(pinDesc.ulPWMChannel);
+        TCCx->CTRLBSET.bit.LUPD = 1;
+        syncTCC(TCCx);
+        TCCx->CCB[tcChannel].reg = (uint32_t) value;
+        syncTCC(TCCx);
+        TCCx->CTRLBCLR.bit.LUPD = 1;
+        syncTCC(TCCx);
+      }
+    }
 #endif
+      
+    return;
+  }

  // -- Defaults to digital write
  pinMode(pin, OUTPUT);
--- a/cores/arduino/wiring_analog.h
+++ b/cores/arduino/wiring_analog.h
@ -27,21 +27,14 @@ extern "C" {
 /*
 * \brief SAMD products have only one reference for ADC
 */
- // add internal voltages for ATSAMD51 SUPC VREF register
 typedef enum _eAnalogReference
 {
  AR_DEFAULT,
+  AR_INTERNAL,
+  AR_EXTERNAL,
  AR_INTERNAL1V0,
-  AR_INTERNAL1V1,
-  AR_INTERNAL1V2,
-  AR_INTERNAL1V25,
-  AR_INTERNAL2V0,
-  AR_INTERNAL2V2,
-  AR_INTERNAL2V23,
-  AR_INTERNAL2V4,
-  AR_INTERNAL2V5,
  AR_INTERNAL1V65,
-  AR_EXTERNAL
+  AR_INTERNAL2V23
 } eAnalogReference ;


--- a/cores/arduino/wiring_digital.c
+++ b/cores/arduino/wiring_digital.c
@ -30,43 +30,39 @@ void pinMode( uint32_t ulPin, uint32_t ulMode )
    return ;
  }

-  EPortType port = g_APinDescription[ulPin].ulPort;
-  uint32_t pin = g_APinDescription[ulPin].ulPin;
-  uint32_t pinMask = (1ul << pin);
-
  // Set pin mode according to chapter '22.6.3 I/O Pin Configuration'
  switch ( ulMode )
  {
    case INPUT:
      // Set pin to input mode
-      PORT->Group[port].PINCFG[pin].reg=(uint8_t)(PORT_PINCFG_INEN) ;
-      PORT->Group[port].DIRCLR.reg = pinMask ;
+      PORT->Group[g_APinDescription[ulPin].ulPort].PINCFG[g_APinDescription[ulPin].ulPin].reg=(uint8_t)(PORT_PINCFG_INEN) ;
+      PORT->Group[g_APinDescription[ulPin].ulPort].DIRCLR.reg = (uint32_t)(1<<g_APinDescription[ulPin].ulPin) ;
    break ;

    case INPUT_PULLUP:
      // Set pin to input mode with pull-up resistor enabled
-      PORT->Group[port].PINCFG[pin].reg=(uint8_t)(PORT_PINCFG_INEN|PORT_PINCFG_PULLEN) ;
-      PORT->Group[port].DIRCLR.reg = pinMask ;
+      PORT->Group[g_APinDescription[ulPin].ulPort].PINCFG[g_APinDescription[ulPin].ulPin].reg=(uint8_t)(PORT_PINCFG_INEN|PORT_PINCFG_PULLEN) ;
+      PORT->Group[g_APinDescription[ulPin].ulPort].DIRCLR.reg = (uint32_t)(1<<g_APinDescription[ulPin].ulPin) ;

      // Enable pull level (cf '22.6.3.2 Input Configuration' and '22.8.7 Data Output Value Set')
-      PORT->Group[port].OUTSET.reg = pinMask ;
+      PORT->Group[g_APinDescription[ulPin].ulPort].OUTSET.reg = (uint32_t)(1<<g_APinDescription[ulPin].ulPin) ;
    break ;

    case INPUT_PULLDOWN:
      // Set pin to input mode with pull-down resistor enabled
-      PORT->Group[port].PINCFG[pin].reg=(uint8_t)(PORT_PINCFG_INEN|PORT_PINCFG_PULLEN) ;
-      PORT->Group[port].DIRCLR.reg = pinMask ;
+      PORT->Group[g_APinDescription[ulPin].ulPort].PINCFG[g_APinDescription[ulPin].ulPin].reg=(uint8_t)(PORT_PINCFG_INEN|PORT_PINCFG_PULLEN) ;
+      PORT->Group[g_APinDescription[ulPin].ulPort].DIRCLR.reg = (uint32_t)(1<<g_APinDescription[ulPin].ulPin) ;

      // Enable pull level (cf '22.6.3.2 Input Configuration' and '22.8.6 Data Output Value Clear')
-      PORT->Group[port].OUTCLR.reg = pinMask ;
+      PORT->Group[g_APinDescription[ulPin].ulPort].OUTCLR.reg = (uint32_t)(1<<g_APinDescription[ulPin].ulPin) ;
    break ;

    case OUTPUT:
      // enable input, to support reading back values, with pullups disabled
-      PORT->Group[port].PINCFG[pin].reg=(uint8_t)(PORT_PINCFG_INEN) ;
+      PORT->Group[g_APinDescription[ulPin].ulPort].PINCFG[g_APinDescription[ulPin].ulPin].reg=(uint8_t)(PORT_PINCFG_INEN) ;

      // Set pin to output mode
-      PORT->Group[port].DIRSET.reg = pinMask ;
+      PORT->Group[g_APinDescription[ulPin].ulPort].DIRSET.reg = (uint32_t)(1<<g_APinDescription[ulPin].ulPin) ;
    break ;

    default:
--- a/cores/arduino/wiring_private.c
+++ b/cores/arduino/wiring_private.c
@ -107,7 +107,7 @@ int pinPeripheral( uint32_t ulPin, EPioType ulPeripheral )
        // Set new muxing
        PORT->Group[g_APinDescription[ulPin].ulPort].PMUX[g_APinDescription[ulPin].ulPin >> 1].reg = temp|PORT_PMUX_PMUXO( ulPeripheral ) ;
        // Enable port mux
-        PORT->Group[g_APinDescription[ulPin].ulPort].PINCFG[g_APinDescription[ulPin].ulPin].reg |= PORT_PINCFG_PMUXEN | PORT_PINCFG_DRVSTR;
+        PORT->Group[g_APinDescription[ulPin].ulPort].PINCFG[g_APinDescription[ulPin].ulPin].reg |= PORT_PINCFG_PMUXEN ;
      }
      else // even pin
      {
@ -115,7 +115,7 @@ int pinPeripheral( uint32_t ulPin, EPioType ulPeripheral )

        temp = (PORT->Group[g_APinDescription[ulPin].ulPort].PMUX[g_APinDescription[ulPin].ulPin >> 1].reg) & PORT_PMUX_PMUXO( 0xF ) ;
        PORT->Group[g_APinDescription[ulPin].ulPort].PMUX[g_APinDescription[ulPin].ulPin >> 1].reg = temp|PORT_PMUX_PMUXE( ulPeripheral ) ;
-        PORT->Group[g_APinDescription[ulPin].ulPort].PINCFG[g_APinDescription[ulPin].ulPin].reg |= PORT_PINCFG_PMUXEN | PORT_PINCFG_DRVSTR ; // Enable port mux
+        PORT->Group[g_APinDescription[ulPin].ulPort].PINCFG[g_APinDescription[ulPin].ulPin].reg |= PORT_PINCFG_PMUXEN ; // Enable port mux
      }
 #endif
    break ;
--- a/drivers/prewin10/adafruit_circuit_playground_express.cat
+++ b/drivers/prewin10/adafruit_circuit_playground_express.cat
--- a/drivers/prewin10/adafruit_circuit_playground_express.inf
+++ b/drivers/prewin10/adafruit_circuit_playground_express.inf
@ -46,14 +46,6 @@ StartType=3
 ErrorControl=1
 ServiceBinary=%12%\%DRIVERFILENAME%.sys

-[NullInstall.nt]
-; nothing to do for a null driver
-
-[NullInstall.nt.Services]
-; null driver has no service and no service name
-AddService=, 0x00000002
-
-
 ;------------------------------------------------------------------------------
 ;  Vista-64bit Sections
 ;------------------------------------------------------------------------------
@ -81,13 +73,6 @@ StartType=3
 ErrorControl=1
 ServiceBinary=%12%\%DRIVERFILENAME%.sys

-[NullInstall.NTamd64]
-; nothing to do for a null driver
-
-[NullInstall.NTamd64.Services]
-; null driver has no service and no service name
-AddService=, 0x00000002
-

 ;------------------------------------------------------------------------------
 ;  Vendor and Product ID Definitions
@ -102,14 +87,14 @@ AddService=, 0x00000002
 [SourceDisksNames]
 [DeviceList]
 "%DESCRIPTION% UF2 Bootloader (0018:00) BSP"=DriverInstall, USB\VID_239A&PID_0018&MI_00
-"%DESCRIPTION% UF2 WebUSB dummy (0018:04) BSP"=NullInstall, USB\VID_239A&PID_0018&MI_04
+"%DESCRIPTION% UF2 WebUSB dummy (0018:04) BSP"=DriverInstall, USB\VID_239A&PID_0018&MI_00
 "%DESCRIPTION% (0019:00) BSP"=DriverInstall, USB\VID_239A&PID_0019&MI_00
 "%DESCRIPTION% Arduino (8018:00) BSP"=DriverInstall, USB\VID_239A&PID_8018&MI_00
 "%DESCRIPTION% CircuitPython (8019:00) BSP"=DriverInstall, USB\VID_239A&PID_8019&MI_00

 [DeviceList.NTamd64]
 "%DESCRIPTION% UF2 Bootloader (0018:00) BSP"=DriverInstall, USB\VID_239A&PID_0018&MI_00
-"%DESCRIPTION% UF2 WebUSB dummy (0018:04) BSP"=NullInstall, USB\VID_239A&PID_0018&MI_04
+"%DESCRIPTION% UF2 WebUSB dummy (0018:04) BSP"=DriverInstall, USB\VID_239A&PID_0018&MI_00
 "%DESCRIPTION% (0019:00) BSP"=DriverInstall, USB\VID_239A&PID_0019&MI_00
 "%DESCRIPTION% Arduino (8018:00) BSP"=DriverInstall, USB\VID_239A&PID_8018&MI_00
 "%DESCRIPTION% CircuitPython (8019:00) BSP"=DriverInstall, USB\VID_239A&PID_8019&MI_00
--- a/extras/build_all.py
+++ b/extras/build_all.py
@ -1,124 +0,0 @@
-import os
-import glob
-import sys
-import subprocess
-import time
-import argparse
-
-FQBN_PREFIX='adafruit:samd:adafruit_'
-
-
-parser = argparse.ArgumentParser(
-    description='python wrapper for adafruit arduino CI workflows',
-    allow_abbrev=False
-    )
-parser.add_argument(
-    '--all_warnings', '--Wall',
-    action='store_true',
-    help='build with all warnings enabled (`--warnings all`)',
-    )
-parser.add_argument(
-    '--warnings_do_not_cause_job_failure',
-    action='store_true',
-    help='failed builds will be listed as failed, but not cause job to exit with an error status',
-    )
-parser.add_argument(
-    'build_boards',
-    metavar='board',
-    nargs='*',
-    help='list of boards to be built -- Note that the fqbn is created by prepending "{}"'.format(FQBN_PREFIX),
-    default= [ 'metro_m0', 'metro_m4', 'circuitplayground_m0' ]
-    )
-args = parser.parse_args()
-
-exit_status = 0
-success_count = 0
-fail_count = 0
-skip_count = 0
-build_format = '| {:22} | {:30} | {:9} '
-build_separator = '-' * 80
-
-def errorOutputFilter(line: str):
-    if len(line) == 0:
-        return False
-    if line.isspace(): # Note: empty string does not match here!
-        return False
-    # TODO: additional items to remove?
-    return True
-
-def build_examples(variant: str):
-    global args, exit_status, success_count, fail_count, skip_count, build_format, build_separator
-
-    print('\n')
-    print(build_separator)
-    print('| {:^76} |'.format('Board ' + variant))
-    print(build_separator)
-    print((build_format + '| {:6} |').format('Library', 'Example', 'Result', 'Time'))
-    print(build_separator)
-    
-    fqbn = "{}{}".format(FQBN_PREFIX, variant)
-
-    for sketch in glob.iglob('libraries/**/*.ino', recursive=True):
-        start_time = time.monotonic()
-
-        # Skip if contains: ".board.test.skip" or ".all.test.skip"
-        # Skip if not contains: ".board.test.only" for a specific board
-        sketchdir = os.path.dirname(sketch)
-        if os.path.exists(sketchdir + '/.all.test.skip') or os.path.exists(sketchdir + '/.' + variant + '.test.skip'):
-            success = "\033[33mskipped\033[0m  "
-        elif glob.glob(sketchdir+"/.*.test.only") and not os.path.exists(sketchdir + '/.build.' + variant):
-            success = "\033[33mskipped\033[0m  "
-        else:
-            # TODO - preferably, would have STDERR show up in **both** STDOUT and STDERR.
-            #        preferably, would use Python logging handler to get both distinct outputs and one merged output
-            #        for now, split STDERR when building with all warnings enabled, so can detect warning/error output.
-            if args.all_warnings:
-                build_result = subprocess.run("arduino-cli compile --warnings all --fqbn {} {}".format(fqbn, sketch), shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-            else:
-                build_result = subprocess.run("arduino-cli compile --warnings default --fqbn {} {}".format(fqbn, sketch), shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
-
-            # get stderr into a form where len(warningLines) indicates a true warning was output to stderr
-            warningLines = [];
-            if args.all_warnings and build_result.stderr:
-                tmpWarningLines = build_result.stderr.decode("utf-8").splitlines()
-                warningLines = list(filter(errorOutputFilter, (tmpWarningLines)))
-
-            if build_result.returncode != 0:
-                exit_status = build_result.returncode
-                success = "\033[31mfailed\033[0m   "
-                fail_count += 1
-            elif len(warningLines) != 0:
-                if not args.warnings_do_not_cause_job_failure:
-                    exit_status = -1
-                success = "\033[31mwarnings\033[0m "
-                fail_count += 1
-            else:
-                success = "\033[32msucceeded\033[0m"
-                success_count += 1
-
-        build_duration = time.monotonic() - start_time
-
-        print((build_format + '| {:5.2f}s |').format(sketch.split(os.path.sep)[1], os.path.basename(sketch), success, build_duration))
-
-        if success != "\033[33mskipped\033[0m  ":
-            if build_result.returncode != 0:
-                print(build_result.stdout.decode("utf-8"))
-                if (build_result.stderr):
-                    print(build_result.stderr.decode("utf-8"))
-            if len(warningLines) != 0:
-                for line in warningLines:
-                    print(line)
-        else:
-            skip_count += 1
-
-build_time = time.monotonic()
-
-for board in args.build_boards:
-    build_examples(board)
-
-print(build_separator)
-build_time = time.monotonic() - build_time
-print("Build Summary: {} \033[32msucceeded\033[0m, {} \033[31mfailed\033[0m, {} \033[33mskipped\033[0m and took {:.2f}s".format(success_count, fail_count, skip_count, build_time))
-print(build_separator)
-
-sys.exit(exit_status)
--- a/keywords.txt
+++ b/keywords.txt
@ -1,3 +1,2 @@
 SerialGSM	KEYWORD1
-SerialSARA	KEYWORD1
 INPUT_PULLDOWN	LITERAL1	Constants	RESERVED_WORD_2
--- a/libraries/Adafruit_ZeroDMA/Adafruit_ZeroDMA.cpp
+++ b/libraries/Adafruit_ZeroDMA/Adafruit_ZeroDMA.cpp
@ -1,654 +0,0 @@
-#include <Adafruit_ZeroDMA.h>
-#include <malloc.h> // memalign() function
-
-#include "utility/dma.h"
-static volatile uint32_t _channelMask = 0; // Bitmask of allocated channels
-
-// DMA descriptor list entry point (and writeback buffer) per channel
-__attribute__((__aligned__(16))) static DmacDescriptor // 128 bit alignment
-  _descriptor[DMAC_CH_NUM] SECTION_DMAC_DESCRIPTOR,
-  _writeback[DMAC_CH_NUM]  SECTION_DMAC_DESCRIPTOR;
-
-// Pointer to ZeroDMA object for each channel is needed for the
-// ISR (in C, outside of class context) to access callbacks.
-static Adafruit_ZeroDMA *_dmaPtr[DMAC_CH_NUM] = { 0 }; // Init to NULL
-
-// Adapted from ASF3 interrupt_sam_nvic.c:
-
-static volatile unsigned long cpu_irq_critical_section_counter = 0;
-static volatile unsigned char cpu_irq_prev_interrupt_state     = 0;
-
-static void cpu_irq_enter_critical(void) {
-    if(!cpu_irq_critical_section_counter) {
-        if(__get_PRIMASK() == 0) { // IRQ enabled?
-            __disable_irq();   // Disable it
-            __DMB();
-            cpu_irq_prev_interrupt_state = 1;
-        } else {
-            // Make sure the to save the prev state as false
-            cpu_irq_prev_interrupt_state = 0;
-        }
-    }
-
-    cpu_irq_critical_section_counter++;
-}
-
-static void cpu_irq_leave_critical(void) {
-    // Check if the user is trying to leave a critical section
-    // when not in a critical section
-    if(cpu_irq_critical_section_counter > 0) {
-        cpu_irq_critical_section_counter--;
-
-        // Only enable global interrupts when the counter
-        // reaches 0 and the state of the global interrupt flag
-        // was enabled when entering critical state */
-        if((!cpu_irq_critical_section_counter) &&
-            cpu_irq_prev_interrupt_state) {
-                __DMB();
-                __enable_irq();
-        }
-    }
-}
-
-// CONSTRUCTOR -------------------------------------------------------------
-
-// Constructor initializes Adafruit_ZeroDMA basics but does NOT allocate a
-// DMA channel (that's done in allocate()) or start a job (that's done in
-// startJob()).  This is because constructors in a global context are called
-// before a sketch's setup() function, which may have some other hardware
-// initialization of its own, don't want it clobbering us.
-Adafruit_ZeroDMA::Adafruit_ZeroDMA(void) {
-    channel           = 0xFF;  // Channel not yet allocated
-    jobStatus         = DMA_STATUS_OK;
-    hasDescriptors    = false; // No descriptors allocated yet
-    loopFlag          = false;
-    peripheralTrigger = 0;     // Software trigger only by default
-    triggerAction     = DMA_TRIGGER_ACTON_TRANSACTION;
-    memset(callback, 0, sizeof(callback));
-}
-
-// TODO: add destructor? Should stop job, delete descriptors, free channel.
-
-// INTERRUPT SERVICE ROUTINE -----------------------------------------------
-
-// This is a C function that exists outside the Adafruit_ZeroDMA context.
-// DMA channel number is determined from the INTPEND register, from this
-// we get a ZeroDMA object pointer through the _dmaPtr[] array.
-// (It's done this way because jobStatus and callback[] are protected
-// elements in the ZeroDMA object -- we can't touch them in C, but the
-// next function after this, being part of the ZeroDMA class, can.)
-
-#ifdef __SAMD51__
-void DMAC_0_Handler(void) {
-#else
-void DMAC_Handler(void) {
-#endif
-    cpu_irq_enter_critical();
-
-    uint8_t channel = DMAC->INTPEND.bit.ID; // Channel # causing interrupt
-    if(channel < DMAC_CH_NUM) {
-        Adafruit_ZeroDMA *dma;
-        if((dma = _dmaPtr[channel])) { // -> Channel's ZeroDMA object
-#ifdef __SAMD51__
-            // Call IRQ handler with channel #
-            dma->_IRQhandler(channel);
-#else
-            DMAC->CHID.bit.ID = channel;
-            // Call IRQ handler with interrupt flag(s)
-            dma->_IRQhandler(DMAC->CHINTFLAG.reg);
-#endif
-        }
-    }
-
-    cpu_irq_leave_critical();
-}
-
-#ifdef __SAMD51__
-void DMAC_1_Handler(void) __attribute__((weak, alias("DMAC_0_Handler")));
-void DMAC_2_Handler(void) __attribute__((weak, alias("DMAC_0_Handler")));
-void DMAC_3_Handler(void) __attribute__((weak, alias("DMAC_0_Handler")));
-void DMAC_4_Handler(void) __attribute__((weak, alias("DMAC_0_Handler")));
-#endif
-
-void Adafruit_ZeroDMA::_IRQhandler(uint8_t flags) {
-#ifdef __SAMD51__
-    // 'flags' is initially passed in as channel number,
-    // from which we look up the actual interrupt flags...
-    flags = DMAC->Channel[flags].CHINTFLAG.reg;
-#endif
-    if(flags & DMAC_CHINTENCLR_TERR) {
-        // Clear error flag
-#ifdef __SAMD51__
-        DMAC->Channel[channel].CHINTFLAG.reg = DMAC_CHINTENCLR_TERR;
-#else
-        DMAC->CHINTFLAG.reg = DMAC_CHINTENCLR_TERR;
-#endif
-        jobStatus           = DMA_STATUS_ERR_IO;
-        if(callback[DMA_CALLBACK_TRANSFER_ERROR]) {
-            callback[DMA_CALLBACK_TRANSFER_ERROR](this);
-        }
-    } else if(flags & DMAC_CHINTENCLR_TCMPL) {
-        // Clear transfer complete flag
-#ifdef __SAMD51__
-        DMAC->Channel[channel].CHINTFLAG.reg = DMAC_CHINTENCLR_TCMPL;
-#else
-        DMAC->CHINTFLAG.reg = DMAC_CHINTENCLR_TCMPL;
-#endif
-        jobStatus           = DMA_STATUS_OK;
-        if(callback[DMA_CALLBACK_TRANSFER_DONE]) {
-            callback[DMA_CALLBACK_TRANSFER_DONE](this);
-        }
-    } else if(flags & DMAC_CHINTENCLR_SUSP) {
-        // Clear channel suspend flag
-#ifdef __SAMD51__
-        DMAC->Channel[channel].CHINTFLAG.reg = DMAC_CHINTENCLR_SUSP;
-#else
-        DMAC->CHINTFLAG.reg = DMAC_CHINTENCLR_SUSP;
-#endif
-        jobStatus           = DMA_STATUS_SUSPEND;
-        if(callback[DMA_CALLBACK_CHANNEL_SUSPEND]) {
-            callback[DMA_CALLBACK_CHANNEL_SUSPEND](this);
-        }
-    }
-}
-
-// DMA CHANNEL FUNCTIONS ---------------------------------------------------
-
-// Allocates channel for ZeroDMA object
-ZeroDMAstatus Adafruit_ZeroDMA::allocate(void) {
-
-    if(channel < DMAC_CH_NUM) return DMA_STATUS_OK; // Already alloc'd!
-
-    // Find index of first free DMA channel.  As currently written,
-    // this "does not play well with others" as it assumes _channelMask
-    // is the final arbiter of channels in use (this is true only within
-    // this library -- but other DMA-driven code may have allocated its
-    // own channel(s) elsewhere, sometimes with an equally broken
-    // approach).  A possible alternate approach, I haven't tested this
-    // yet, might be to loop through each channel, set DMAC->CHID.bit.ID
-    // and then test whether CHCTRLA.bit.ENABLE is set?  But for now...
-    for(channel=0; (channel < DMAC_CH_NUM) &&
-      (_channelMask & (1 << channel)); channel++);
-    // Doesn't help that code later does a software reset of the DMA
-    // controller, which would blow out other DMA-using libraries
-    // anyway (or they're just as likely to blow out this one).
-    // I think it's just an all-or-nothing affair...use one library
-    // for DMA everything, never mix and match.
-
-    if(channel >= DMAC_CH_NUM) { // No free channel!
-        return DMA_STATUS_ERR_NOT_FOUND;
-    }
-
-    cpu_irq_enter_critical();
-
-    if(!_channelMask) { // No channels allocated yet; initialize DMA!
-#if (SAML21) || (SAML22) || (SAMC20) || (SAMC21)
-        PM->AHBMASK.bit.DMAC_       = 1;
-#elif defined(__SAMD51__)
-        MCLK->AHBMASK.bit.DMAC_     = 1; // Initialize DMA clocks
-#else
-        PM->AHBMASK.bit.DMAC_       = 1; // Initialize DMA clocks
-        PM->APBBMASK.bit.DMAC_      = 1;
-#endif
-        DMAC->CTRL.bit.DMAENABLE    = 0; // Disable DMA controller
-        DMAC->CTRL.bit.SWRST        = 1; // Perform software reset
-
-        // Initialize descriptor list addresses
-        DMAC->BASEADDR.bit.BASEADDR = (uint32_t)_descriptor;
-        DMAC->WRBADDR.bit.WRBADDR   = (uint32_t)_writeback;
-        memset(_descriptor, 0, sizeof(_descriptor));
-        memset(_writeback , 0, sizeof(_writeback));
-
-        // Re-enable DMA controller with all priority levels
-        DMAC->CTRL.reg = DMAC_CTRL_DMAENABLE | DMAC_CTRL_LVLEN(0xF);
-
-        // Enable DMA interrupt at lowest priority
-#ifdef __SAMD51__
-        IRQn_Type irqs[] = { DMAC_0_IRQn, DMAC_1_IRQn, DMAC_2_IRQn,
-                             DMAC_3_IRQn, DMAC_4_IRQn };
-        for(uint8_t i=0; i<(sizeof irqs / sizeof irqs[0]); i++) {
-            NVIC_EnableIRQ(irqs[i]);
-            NVIC_SetPriority(irqs[i], (1<<__NVIC_PRIO_BITS)-1);
-        }
-#else
-        NVIC_EnableIRQ(DMAC_IRQn);
-        NVIC_SetPriority(DMAC_IRQn, (1 << __NVIC_PRIO_BITS) - 1);
-#endif
-    }
-
-    _channelMask    |= 1 << channel; // Mark channel as allocated
-    _dmaPtr[channel] = this;         // Channel-index-to-object pointer
-
-    // Reset the allocated channel
-#ifdef __SAMD51__
-    DMAC->Channel[channel].CHCTRLA.bit.ENABLE  = 0;
-    DMAC->Channel[channel].CHCTRLA.bit.SWRST   = 1;
-#else
-    DMAC->CHID.bit.ID         = channel;
-    DMAC->CHCTRLA.bit.ENABLE  = 0;
-    DMAC->CHCTRLA.bit.SWRST   = 1;
-#endif
-
-    // Clear software trigger
-    DMAC->SWTRIGCTRL.reg     &= ~(1 << channel);
-
-    // Configure default behaviors
-#ifdef __SAMD51__
-    DMAC->Channel[channel].CHPRILVL.bit.PRILVL = 0;
-    DMAC->Channel[channel].CHCTRLA.bit.TRIGSRC = peripheralTrigger;
-    DMAC->Channel[channel].CHCTRLA.bit.TRIGACT = triggerAction;
-    DMAC->Channel[channel].CHCTRLA.bit.BURSTLEN =
-      DMAC_CHCTRLA_BURSTLEN_SINGLE_Val; // Single-beat burst length
-#else
-    DMAC->CHCTRLB.bit.LVL     = 0;
-    DMAC->CHCTRLB.bit.TRIGSRC = peripheralTrigger;
-    DMAC->CHCTRLB.bit.TRIGACT = triggerAction;
-#endif
-
-    cpu_irq_leave_critical();
-
-    return DMA_STATUS_OK;
-}
-
-void Adafruit_ZeroDMA::setPriority(dma_priority pri) const {
-#ifdef __SAMD51__
-    DMAC->Channel[channel].CHPRILVL.bit.PRILVL = pri;
-#else
-    DMAC->CHCTRLB.bit.LVL = pri;
-#endif
-}
-
-// Deallocate DMA channel
-// TODO: should this delete/deallocate the descriptor list?
-ZeroDMAstatus Adafruit_ZeroDMA::free(void) {
-
-    ZeroDMAstatus status = DMA_STATUS_OK;
-
-    cpu_irq_enter_critical(); // jobStatus is volatile
-
-    if(jobStatus == DMA_STATUS_BUSY) {
-        status = DMA_STATUS_BUSY; // Can't leave when busy
-    } else if((channel < DMAC_CH_NUM) && (_channelMask & (1 << channel))) {
-        // Valid in-use channel; release it
-        _channelMask &= ~(1 << channel); // Clear bit
-        if(!_channelMask) {              // No more channels in use?
-#ifdef __SAMD51__
-            NVIC_DisableIRQ(DMAC_0_IRQn); // Disable DMA interrupt
-            DMAC->CTRL.bit.DMAENABLE = 0; // Disable DMA
-            MCLK->AHBMASK.bit.DMAC_  = 0; // Disable DMA clock
-#else
-            NVIC_DisableIRQ(DMAC_IRQn);   // Disable DMA interrupt
-            DMAC->CTRL.bit.DMAENABLE = 0; // Disable DMA
-            PM->APBBMASK.bit.DMAC_   = 0; // Disable DMA clocks
-            PM->AHBMASK.bit.DMAC_    = 0;
-#endif
-        }
-        _dmaPtr[channel] = NULL;
-        channel          = 0xFF;
-    } else {
-        status = DMA_STATUS_ERR_NOT_INITIALIZED; // Channel not in use
-    }
-
-    cpu_irq_leave_critical();
-
-    return status;
-}
-
-// Start DMA transfer job.  Channel and descriptors should be allocated
-// before calling this.
-ZeroDMAstatus Adafruit_ZeroDMA::startJob(void) {
-    ZeroDMAstatus status = DMA_STATUS_OK;
-
-    cpu_irq_enter_critical(); // Job status is volatile
-
-    if(jobStatus == DMA_STATUS_BUSY) {
-        status = DMA_STATUS_BUSY; // Resource is busy
-    } else if(channel >= DMAC_CH_NUM) {
-        status = DMA_STATUS_ERR_NOT_INITIALIZED; // Channel not in use
-    } else if(!hasDescriptors || (_descriptor[channel].BTCNT.reg <= 0)) {
-        status = DMA_STATUS_ERR_INVALID_ARG; // Bad transfer size
-    } else {
-        uint8_t i, interruptMask = 0;
-        for(i=0; i<DMA_CALLBACK_N; i++) {
-            if(callback[i]) interruptMask |= (1 << i);
-        }
-        jobStatus            = DMA_STATUS_BUSY;
-#ifdef __SAMD51__
-        DMAC->Channel[channel].CHINTENSET.reg =
-          DMAC_CHINTENSET_MASK &  interruptMask;
-        DMAC->Channel[channel].CHINTENCLR.reg =
-          DMAC_CHINTENCLR_MASK & ~interruptMask;
-        DMAC->Channel[channel].CHCTRLA.bit.ENABLE = 1;
-#else
-        DMAC->CHID.bit.ID    = channel;
-        DMAC->CHINTENSET.reg = DMAC_CHINTENSET_MASK &  interruptMask;
-        DMAC->CHINTENCLR.reg = DMAC_CHINTENCLR_MASK & ~interruptMask;
-        DMAC->CHCTRLA.bit.ENABLE = 1; // Enable the transfer channel
-#endif
-    }
-
-    cpu_irq_leave_critical();
-
-    return status;
-}
-
-// Set and enable callback function for ZeroDMA object. This can be called
-// before or after channel and/or descriptors are allocated, but needs
-// to be called before job is started.
-void Adafruit_ZeroDMA::setCallback(
-  void (*cb)(Adafruit_ZeroDMA *), dma_callback_type type) {
-    callback[type] = cb;
-}
-
-// Suspend/resume don't quite do what I thought -- avoid using for now.
-void Adafruit_ZeroDMA::suspend(void) const {
-    cpu_irq_enter_critical();
-#ifdef __SAMD51__
-    DMAC->Channel[channel].CHCTRLB.reg |= DMAC_CHCTRLB_CMD_SUSPEND;
-#else
-    DMAC->CHID.bit.ID  = channel;
-    DMAC->CHCTRLB.reg |= DMAC_CHCTRLB_CMD_SUSPEND;
-#endif
-    cpu_irq_leave_critical();
-}
-
-#define MAX_JOB_RESUME_COUNT 10000
-void Adafruit_ZeroDMA::resume(void) {
-    cpu_irq_enter_critical(); // jobStatus is volatile
-    if(jobStatus == DMA_STATUS_SUSPEND) {
-        int      count;
-        uint32_t bitMask   = 1 << channel;
-#ifdef __SAMD51__
-        DMAC->Channel[channel].CHCTRLB.reg |= DMAC_CHCTRLB_CMD_RESUME;
-#else
-        DMAC->CHID.bit.ID  = channel;
-        DMAC->CHCTRLB.reg |= DMAC_CHCTRLB_CMD_RESUME;
-#endif
-
-        for(count = 0; (count < MAX_JOB_RESUME_COUNT) &&
-          !(DMAC->BUSYCH.reg & bitMask); count++);
-
-        jobStatus = (count < MAX_JOB_RESUME_COUNT) ?
-          DMA_STATUS_BUSY : DMA_STATUS_ERR_TIMEOUT;
-    }
-    cpu_irq_leave_critical();
-}
-
-// Abort is OK though.
-void Adafruit_ZeroDMA::abort(void) {
-    if(channel <= DMAC_CH_NUM) {
-        cpu_irq_enter_critical();
-#ifdef __SAMD51__
-        DMAC->Channel[channel].CHCTRLA.reg = 0; // Disable channel
-#else
-        DMAC->CHID.bit.ID = channel; // Select channel
-        DMAC->CHCTRLA.reg = 0;       // Disable
-#endif
-        jobStatus         = DMA_STATUS_ABORTED;
-        cpu_irq_leave_critical();
-    }
-}
-
-// Set DMA peripheral trigger.
-// This can be done before or after channel is allocated.
-void Adafruit_ZeroDMA::setTrigger(uint8_t trigger) {
-    peripheralTrigger = trigger; // Save value for allocate()
-
-    // If channel already allocated, configure peripheral trigger
-    // (old lib required configure before alloc -- either way OK now)
-    if(channel < DMAC_CH_NUM) {
-        cpu_irq_enter_critical();
-#ifdef __SAMD51__
-        DMAC->Channel[channel].CHCTRLA.bit.TRIGSRC = trigger;
-#else
-        DMAC->CHID.bit.ID         = channel;
-        DMAC->CHCTRLB.bit.TRIGSRC = trigger;
-#endif
-        cpu_irq_leave_critical();
-    }
-}
-
-// Set DMA trigger action.
-// This can be done before or after channel is allocated.
-void Adafruit_ZeroDMA::setAction(dma_transfer_trigger_action action) {
-    triggerAction = action; // Save value for allocate()
-
-    // If channel already allocated, configure trigger action
-    // (old lib required configure before alloc -- either way OK now)
-    if(channel < DMAC_CH_NUM) {
-        cpu_irq_enter_critical();
-#ifdef __SAMD51__
-        DMAC->Channel[channel].CHCTRLA.bit.TRIGACT = action;
-#else
-        DMAC->CHID.bit.ID         = channel;
-        DMAC->CHCTRLB.bit.TRIGACT = action;
-#endif
-        cpu_irq_leave_critical();
-    }
-}
-
-// Issue software trigger. Channel must be allocated & descriptors added!
-void Adafruit_ZeroDMA::trigger(void) const {
-    if((channel <= DMAC_CH_NUM) & hasDescriptors) {
-        DMAC->SWTRIGCTRL.reg |= (1 << channel);
-    }
-}
-
-// Returns true if DMA transfer in progress.
-bool Adafruit_ZeroDMA::isActive(void) const {
-    return _writeback[channel].BTCTRL.bit.VALID;
-}
-
-// DMA DESCRIPTOR FUNCTIONS ------------------------------------------------
-
-// Allocates a new DMA descriptor (if needed) and appends it to the
-// channel's descriptor list.  Returns pointer to DmacDescriptor,
-// or NULL on various errors.  You'll want to keep the pointer for
-// later if you need to modify or free the descriptor.
-// Channel must be allocated first!
-DmacDescriptor *Adafruit_ZeroDMA::addDescriptor(
-  void           *src,
-  void           *dst,
-  uint32_t        count,
-  dma_beat_size   size,
-  bool            srcInc,
-  bool            dstInc,
-  uint32_t        stepSize,
-  bool            stepSel) {
-
-    // Channel must be allocated first
-       if(channel >= DMAC_CH_NUM) return NULL;
-
-    // Can't do while job's busy
-    if(jobStatus == DMA_STATUS_BUSY) return NULL;
-
-    DmacDescriptor *desc;
-
-    // Scan descriptor list to find last entry.  If an entry's
-    // DESCADDR value is 0, that's the end of the list and it's
-    // currently un-looped.  If the DESCADDR value is the same
-    // as the first entry, that's the end of the list and it's
-    // looped.  Either way, set the last entry's DESCADDR value
-    // to the new descriptor, and the descriptor's own DESCADDR
-    // will be set later either to 0 or the list head.
-    if(hasDescriptors) {
-        // DMA descriptors must be 128-bit (16 byte) aligned.
-        // memalign() is considered 'obsolete' but it's replacements
-        // (aligned_alloc() or posix_memalign()) are not currently
-        // available in the version of ARM GCC in use, but this is,
-        // so here we are.
-        if(!(desc = (DmacDescriptor *)memalign(16, sizeof(DmacDescriptor)))) {
-            return NULL;
-        }
-        DmacDescriptor *prev = &_descriptor[channel];
-        while(prev->DESCADDR.reg &&
-             (prev->DESCADDR.reg != (uint32_t)&_descriptor[channel])) {
-            prev = (DmacDescriptor *)prev->DESCADDR.reg;
-        }
-        prev->DESCADDR.reg = (uint32_t)desc;
-    } else {
-        desc = &_descriptor[channel];
-    }
-    hasDescriptors = true;
-
-    uint8_t bytesPerBeat; // Beat transfer size IN BYTES
-    switch(size) {
-       default:                  bytesPerBeat = 1; break;
-       case DMA_BEAT_SIZE_HWORD: bytesPerBeat = 2; break;
-       case DMA_BEAT_SIZE_WORD:  bytesPerBeat = 4; break;
-    }
-
-    desc->BTCTRL.bit.VALID     = true;
-    desc->BTCTRL.bit.EVOSEL    = DMA_EVENT_OUTPUT_DISABLE;
-    desc->BTCTRL.bit.BLOCKACT  = DMA_BLOCK_ACTION_NOACT;
-    desc->BTCTRL.bit.BEATSIZE  = size;
-    desc->BTCTRL.bit.SRCINC    = srcInc;
-    desc->BTCTRL.bit.DSTINC    = dstInc;
-    desc->BTCTRL.bit.STEPSEL   = stepSel;
-    desc->BTCTRL.bit.STEPSIZE  = stepSize;
-    desc->BTCNT.reg            = count;
-    desc->SRCADDR.reg          = (uint32_t)src;
-
-    if(srcInc) {
-        if(stepSel) {
-            desc->SRCADDR.reg += bytesPerBeat * count * (1 << stepSize);
-        } else {
-            desc->SRCADDR.reg += bytesPerBeat * count;
-        }
-    }
-
-    desc->DSTADDR.reg          = (uint32_t)dst;
-
-    if(dstInc) {
-        if(!stepSel) {
-            desc->DSTADDR.reg += bytesPerBeat * count * (1 << stepSize);
-        } else {
-            desc->DSTADDR.reg += bytesPerBeat * count;
-        }
-    }
-
-    desc->DESCADDR.reg = loopFlag ? (uint32_t)&_descriptor[channel] : 0;
-
-    return desc;
-}
-
-// Modify DMA descriptor with a new source address, destination address &
-// block transfer count.  All other attributes (including increment enables,
-// etc.) are unchanged.  Mostly for changing the data being pushed to a
-// peripheral (DAC, SPI, whatev.)
-void Adafruit_ZeroDMA::changeDescriptor(DmacDescriptor *desc,
-  void *src, void *dst, uint32_t count) {
-
-    uint8_t bytesPerBeat; // Beat transfer size IN BYTES
-    switch(desc->BTCTRL.bit.BEATSIZE) {
-       default:                  bytesPerBeat = 1; break;
-       case DMA_BEAT_SIZE_HWORD: bytesPerBeat = 2; break;
-       case DMA_BEAT_SIZE_WORD:  bytesPerBeat = 4; break;
-    }
-
-    if(count) desc->BTCNT.reg = count;
-
-    if(src) {
-        desc->SRCADDR.reg = (uint32_t)src;
-        if(desc->BTCTRL.bit.SRCINC) {
-            if(desc->BTCTRL.bit.STEPSEL) {
-                desc->SRCADDR.reg += desc->BTCNT.reg *
-                  bytesPerBeat * (1 << desc->BTCTRL.bit.STEPSIZE);
-            } else {
-                desc->SRCADDR.reg += desc->BTCNT.reg * bytesPerBeat;
-            }
-        }
-    }
-
-    if(dst) {
-        desc->DSTADDR.reg = (uint32_t)dst;
-        if(desc->BTCTRL.bit.DSTINC) {
-            if(!desc->BTCTRL.bit.STEPSEL) {
-                desc->DSTADDR.reg += desc->BTCNT.reg *
-                  bytesPerBeat * (1 << desc->BTCTRL.bit.STEPSIZE);
-            } else {
-                desc->DSTADDR.reg += desc->BTCNT.reg * bytesPerBeat;
-            }
-        }
-    }
-
-// I think this code is here by accident -- disabling for now.
-#if 0
-    cpu_irq_enter_critical();
-    jobStatus          = DMA_STATUS_OK;
-#ifdef __SAMD51__
-    DMAC->Channel[channel].CHCTRLA.bit.ENABLE = 1;
-#else
-    DMAC->CHID.bit.ID  = channel;
-    DMAC->CHCTRLA.reg |= DMAC_CHCTRLA_ENABLE;
-#endif
-    cpu_irq_leave_critical();
-#endif
-}
-
-// TODO: delete descriptor, delete whole descriptor chain
-
-// Select whether channel's descriptor list should repeat or not.
-// This can be done before or after channel & any descriptors are allocated.
-void Adafruit_ZeroDMA::loop(boolean flag) {
-    // The loop selection is 'sticky' -- that is, you can enable or
-    // disable looping before a descriptor list is built, or after
-    // the fact.  This requires some extra steps in the library code
-    // but avoids a must-do-in-X-order constraint on user.
-    loopFlag = flag;
-
-    if(hasDescriptors) { // Descriptor list already started?
-        // Scan descriptor list to find last entry.  If an entry's
-        // DESCADDR value is 0, that's the end of the list and it's
-        // currently un-looped.  If the DESCADDR value is the same
-        // as the first entry, that's the end of the list and it's
-        // already looped.
-        DmacDescriptor *desc = &_descriptor[channel];
-        while(desc->DESCADDR.reg &&
-          (desc->DESCADDR.reg != (uint32_t)&_descriptor[channel])) {
-            desc = (DmacDescriptor *)desc->DESCADDR.reg;
-        }
-        // Loop or unloop descriptor list as appropriate
-        desc->DESCADDR.reg = loopFlag ?  (uint32_t)&_descriptor[channel] : 0;
-    }
-}
-
-// MISCELLANY --------------------------------------------------------------
-
-void Adafruit_ZeroDMA::printStatus(ZeroDMAstatus s) const {
-    if(s == DMA_STATUS_JOBSTATUS) s = jobStatus;
-    Serial.print("Status: ");
-    switch(s) {
-       case DMA_STATUS_OK:
-            Serial.println("OK");
-            break;
-       case DMA_STATUS_ERR_NOT_FOUND:
-            Serial.println("NOT FOUND");
-            break;
-       case DMA_STATUS_ERR_NOT_INITIALIZED:
-            Serial.println("NOT INITIALIZED");
-            break;
-       case DMA_STATUS_ERR_INVALID_ARG:
-            Serial.println("INVALID ARGUMENT");
-            break;
-       case DMA_STATUS_ERR_IO:
-            Serial.println("IO ERROR");
-            break;
-       case DMA_STATUS_ERR_TIMEOUT:
-            Serial.println("TIMEOUT");
-            break;
-       case DMA_STATUS_BUSY:
-            Serial.println("BUSY");
-            break;
-       case DMA_STATUS_SUSPEND:
-            Serial.println("SUSPENDED");
-            break;
-       case DMA_STATUS_ABORTED:
-            Serial.println("ABORTED");
-            break;
-       default:
-            Serial.print("Unknown 0x");
-            Serial.println((int)s);
-            break;
-    }
-}
--- a/libraries/Adafruit_ZeroDMA/Adafruit_ZeroDMA.h
+++ b/libraries/Adafruit_ZeroDMA/Adafruit_ZeroDMA.h
@ -1,66 +0,0 @@
-#ifndef _ADAFRUIT_ZERODMA_H_
-#define _ADAFRUIT_ZERODMA_H_
-
-#include "Arduino.h"
-#include "utility/dma.h"
-
-// Status codes returned by some DMA functions and/or held in
-// a channel's jobStatus variable.
-enum ZeroDMAstatus {
-    DMA_STATUS_OK = 0,
-    DMA_STATUS_ERR_NOT_FOUND,
-    DMA_STATUS_ERR_NOT_INITIALIZED,
-    DMA_STATUS_ERR_INVALID_ARG,
-    DMA_STATUS_ERR_IO,
-    DMA_STATUS_ERR_TIMEOUT,
-    DMA_STATUS_BUSY,
-    DMA_STATUS_SUSPEND,
-    DMA_STATUS_ABORTED,
-    DMA_STATUS_JOBSTATUS = -1 // For printStatus() function
-};
-
-class Adafruit_ZeroDMA {
- public:
-  Adafruit_ZeroDMA(void);
-
-  // DMA channel functions
-  ZeroDMAstatus   allocate(void), // Allocates DMA channel
-                  startJob(void),
-                  free(void);     // Deallocates DMA channel
-  void            trigger(void) const,
-                  setTrigger(uint8_t trigger),
-                  setAction(dma_transfer_trigger_action action),
-                  setCallback(void (*callback)(Adafruit_ZeroDMA *) = NULL,
-                    dma_callback_type type = DMA_CALLBACK_TRANSFER_DONE),
-                  loop(boolean flag),
-                  suspend(void) const,
-                  resume(void),
-                  abort(void),
-                  setPriority(dma_priority pri) const,
-                  printStatus(ZeroDMAstatus s = DMA_STATUS_JOBSTATUS) const;
-  uint8_t         getChannel(void) const { return channel; }
-
-  // DMA descriptor functions
-  DmacDescriptor *addDescriptor(void *src, void *dst, uint32_t count = 0,
-                    dma_beat_size size = DMA_BEAT_SIZE_BYTE,
-                    bool srcInc = true, bool dstInc = true, 
-                    uint32_t stepSize = DMA_ADDRESS_INCREMENT_STEP_SIZE_1, 
-                    bool stepSel = DMA_STEPSEL_DST);
-  void            changeDescriptor(DmacDescriptor *d, void *src = NULL,
-                    void *dst = NULL, uint32_t count = 0);
-  bool            isActive(void) const;
-
-  void            _IRQhandler(uint8_t flags); // DO NOT TOUCH
-
-
- protected:  
-  uint8_t                     channel;
-  volatile enum ZeroDMAstatus jobStatus;
-  bool                        hasDescriptors;
-  bool                        loopFlag;
-  uint8_t                     peripheralTrigger;
-  dma_transfer_trigger_action triggerAction;
-  void                      (*callback[DMA_CALLBACK_N])(Adafruit_ZeroDMA *);
-};
-
-#endif // _ADAFRUIT_ZERODMA_H_
--- a/libraries/Adafruit_ZeroDMA/LICENSE
+++ b/libraries/Adafruit_ZeroDMA/LICENSE
@ -1,22 +0,0 @@
-The MIT License (MIT)
-
-Copyright (c) 2016 Adafruit Industries
-
-Permission is hereby granted, free of charge, to any person obtaining a copy
-of this software and associated documentation files (the "Software"), to deal
-in the Software without restriction, including without limitation the rights
-to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-copies of the Software, and to permit persons to whom the Software is
-furnished to do so, subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.
-
--- a/libraries/Adafruit_ZeroDMA/README.md
+++ b/libraries/Adafruit_ZeroDMA/README.md
@ -1,6 +0,0 @@
-# Adafruit_ZeroDMA
-DMA helper/wrapped for ATSAMD21 such as Arduino Zero &amp; Feather M0
-
-Current version of this library no longer requires Adafruit_ASFcore as a prerequisite. However...IT BREAKS COMPATIBILITY WITH PRIOR VERSIONS. Function names, calling sequence and return types/values have changed. See examples!
-
-Item(s) in 'utility' directory are much pared-down derivatives of Atmel ASFcore 3 files. Please keep their original copyright and license intact when editing.
--- a/libraries/Adafruit_ZeroDMA/examples/zerodma_memcpy/zerodma_memcpy.ino
+++ b/libraries/Adafruit_ZeroDMA/examples/zerodma_memcpy/zerodma_memcpy.ino
@ -1,95 +0,0 @@
-// Simple ZeroDMA example -- an equivalent to the memcpy() function.
-// Decause it uses DMA, unlike memcpy(), your code could be doing other
-// things simultaneously while the copy operation runs.
-
-#include <Adafruit_ZeroDMA.h>
-#include "utility/dma.h"
-
-Adafruit_ZeroDMA myDMA;
-ZeroDMAstatus    stat; // DMA status codes returned by some functions
-
-// The memory we'll be moving:
-#define DATA_LENGTH 1024
-uint8_t source_memory[DATA_LENGTH],
-        destination_memory[DATA_LENGTH];
-
-volatile bool transfer_is_done = false; // Done yet?
-
-// Callback for end-of-DMA-transfer
-void dma_callback(Adafruit_ZeroDMA *dma) {
-  (void)dma; // avoid compiler warning about unused function parameter
-  transfer_is_done = true;
-}
-
-void setup() {
-  uint32_t t;
-  pinMode(LED_BUILTIN, OUTPUT);   // Onboard LED can be used for precise
-  digitalWrite(LED_BUILTIN, LOW); // benchmarking with an oscilloscope
-  Serial.begin(115200);
-  while(!Serial);                 // Wait for Serial monitor before continuing
-
-  Serial.println("DMA test: memory copy");
-
-  Serial.print("Allocating DMA channel...");
-  stat = myDMA.allocate();
-  myDMA.printStatus(stat);
-
-  Serial.println("Setting up transfer");
-  myDMA.addDescriptor(source_memory, destination_memory, DATA_LENGTH);
-
-  Serial.println("Adding callback");
-  // register_callback() can optionally take a second argument
-  // (callback type), default is DMA_CALLBACK_TRANSFER_DONE
-  myDMA.setCallback(dma_callback);
-
-  // Fill the source buffer with incrementing bytes, dest buf with 0's
-  for(uint32_t i=0; i<DATA_LENGTH; i++) source_memory[i] = i;
-  memset(destination_memory, 0, DATA_LENGTH);
-
-  // Show the destination buffer is empty before transfer
-  Serial.println("Destination buffer before transfer:");
-  dump();
-
-  Serial.println("Starting transfer job");
-  stat = myDMA.startJob();
-  myDMA.printStatus(stat);
-
-  Serial.println("Triggering DMA transfer...");
-  t = micros();
-  digitalWrite(LED_BUILTIN, HIGH);
-  myDMA.trigger();
-
-  // Your code could do other things here while copy happens!
-
-  while(!transfer_is_done); // Chill until DMA transfer completes
-
-  digitalWrite(LED_BUILTIN, LOW);
-  t = micros() - t; // Elapsed time
-
-  Serial.print("Done! ");
-  Serial.print(t);
-  Serial.println(" microseconds");
-
-  Serial.println("Destination buffer after transfer:");
-  dump();
-
-  // Now repeat the same operation, but 'manually' using memcpy() (not DMA):
-  t = micros();
-  digitalWrite(LED_BUILTIN, HIGH);
-  memcpy(destination_memory, source_memory,  DATA_LENGTH);
-  digitalWrite(LED_BUILTIN, LOW);
-  t = micros() - t; // Elapsed time
-  Serial.print("Same operation without DMA: ");
-  Serial.print(t);
-  Serial.println(" microseconds");
-}
-
-// Show contents of destination_memory[] array
-void dump() {
-  for(uint32_t i=0; i<DATA_LENGTH; i++) {
-    Serial.print(destination_memory[i], HEX); Serial.print(' ');
-    if ((i & 15) == 15) Serial.println();
-  }
-}
-
-void loop() { }
--- a/libraries/Adafruit_ZeroDMA/examples/zerodma_spi1/zerodma_spi1.ino
+++ b/libraries/Adafruit_ZeroDMA/examples/zerodma_spi1/zerodma_spi1.ino
@ -1,98 +0,0 @@
-// DMA-based SPI buffer write.  This is transmit-only as written, i.e.
-// not equivalent to Arduino's SPI.transfer() which both sends and
-// receives a single byte or word.  Also, this is single-buffered to
-// demonstrate a simple SPI write case.  See zerodma_spi2.ino for an
-// example using double buffering (2 buffers alternating fill & transmit).
-
-#include <SPI.h>
-#include <Adafruit_ZeroDMA.h>
-#include "utility/dma.h"
-
-Adafruit_ZeroDMA myDMA;
-ZeroDMAstatus    stat; // DMA status codes returned by some functions
-
-// The memory we'll be issuing to SPI:
-#define DATA_LENGTH 2048
-uint8_t source_memory[DATA_LENGTH];
-
-volatile bool transfer_is_done = false; // Done yet?
-
-// Callback for end-of-DMA-transfer
-void dma_callback(Adafruit_ZeroDMA *dma) {
-  (void)dma; // avoid compiler warning about unused parameter
-  transfer_is_done = true;
-}
-
-void setup() {
-  uint32_t t;
-  pinMode(LED_BUILTIN, OUTPUT);   // Onboard LED can be used for precise
-  digitalWrite(LED_BUILTIN, LOW); // benchmarking with an oscilloscope
-  Serial.begin(115200);
-  while(!Serial);                 // Wait for Serial monitor before continuing
-
-  Serial.println("DMA test: SPI data out");
-
-  SPI.begin();
-
-  Serial.println("Configuring DMA trigger");
-#ifdef __SAMD51__
-  // SERCOM2 is the 'native' SPI SERCOM on Metro M4
-  myDMA.setTrigger(SERCOM2_DMAC_ID_TX);
-#else
-  // SERCOM4 is the 'native' SPI SERCOM on most M0 boards
-  myDMA.setTrigger(SERCOM4_DMAC_ID_TX);
-#endif
-  myDMA.setAction(DMA_TRIGGER_ACTON_BEAT);
-
-  Serial.print("Allocating DMA channel...");
-  stat = myDMA.allocate();
-  myDMA.printStatus(stat);
-
-  Serial.println("Setting up transfer");
-  myDMA.addDescriptor(
-    source_memory,                    // move data from here
-#ifdef __SAMD51__
-    (void *)(&SERCOM2->SPI.DATA.reg), // to here (M4)
-#else
-    (void *)(&SERCOM4->SPI.DATA.reg), // to here (M0)
-#endif
-    DATA_LENGTH,                      // this many...
-    DMA_BEAT_SIZE_BYTE,               // bytes/hword/words
-    true,                             // increment source addr?
-    false);                           // increment dest addr?
-
-  Serial.println("Adding callback");
-  // register_callback() can optionally take a second argument
-  // (callback type), default is DMA_CALLBACK_TRANSFER_DONE
-  myDMA.setCallback(dma_callback);
-
-  // Fill the source buffer with incrementing bytes
-  for(uint32_t i=0; i<DATA_LENGTH; i++) source_memory[i] = i;
-
-  // Start SPI transaction at 12 MHz
-  SPI.beginTransaction(SPISettings(12000000, MSBFIRST, SPI_MODE0));
-
-  Serial.println("Starting transfer job");
-  t = micros();
-  digitalWrite(LED_BUILTIN, HIGH);
-
-  // Because we've configured a peripheral trigger (SPI), there's
-  // no need to manually trigger transfer, it starts up on its own.
-  stat = myDMA.startJob();
-
-  // Your code could do other things here while SPI write happens!
-
-  while(!transfer_is_done); // Chill until DMA transfer completes
-
-  digitalWrite(LED_BUILTIN, LOW);
-  t = micros() - t; // Elapsed time
-
-  SPI.endTransaction();
-  myDMA.printStatus(stat); // Results of start_transfer_job()
-
-  Serial.print("Done! ");
-  Serial.print(t);
-  Serial.println(" microseconds");
-}
-
-void loop() { }
--- a/libraries/Adafruit_ZeroDMA/examples/zerodma_spi2/zerodma_spi2.ino
+++ b/libraries/Adafruit_ZeroDMA/examples/zerodma_spi2/zerodma_spi2.ino
@ -1,104 +0,0 @@
-// Double-buffered DMA on auxiliary SPI peripheral on pins 11/12/13.
-// Continuously alternates between two data buffers...one is filled
-// with new data as the other is being transmitted.
-
-#include <SPI.h>
-#include <Adafruit_ZeroDMA.h>
-#include "utility/dma.h"
-#include "wiring_private.h" // pinPeripheral() function
-
-// Declare our own SPI peripheral 'mySPI' on pins 11/12/13:
-// (Do not call this SPI1; Arduino Zero and Metro M0 already
-// have an SPI1 (the EDBG interface) and it won't compile.)
-SPIClass mySPI(
-  &sercom1,         // -> Sercom peripheral
-  34,               // MISO pin (also digital pin 12)
-  37,               // SCK pin  (also digital pin 13)
-  35,               // MOSI pin (also digital pin 11)
-  SPI_PAD_0_SCK_1,  // TX pad (MOSI, SCK pads)
-  SERCOM_RX_PAD_3); // RX pad (MISO pad)
-
-Adafruit_ZeroDMA myDMA;
-ZeroDMAstatus    stat; // DMA status codes returned by some functions
-
-// Data we'll issue to mySPI.  There are TWO buffers; one being
-// filled with new data while the other's being transmitted in
-// the background.
-#define DATA_LENGTH 512
-uint8_t source_memory[2][DATA_LENGTH],
-        buffer_being_filled = 0, // Index of 'filling' buffer
-        buffer_value        = 0; // Value of fill
-
-volatile bool transfer_is_done = true; // Done yet?
-
-// Callback for end-of-DMA-transfer
-void dma_callback(Adafruit_ZeroDMA *dma) {
-  (void)dma; // avoid compiler warning about unused parameter
-  transfer_is_done = true;
-}
-
-DmacDescriptor *desc; // DMA descriptor address (so we can change contents)
-
-void setup() {
-  Serial.begin(115200);
-  while(!Serial); // Wait for Serial monitor before continuing
-
-  Serial.println("DMA test: SPI data out");
-
-  mySPI.begin();
-  // Assign pins 11, 12, 13 to SERCOM functionality
-  pinPeripheral(11, PIO_SERCOM);
-  pinPeripheral(12, PIO_SERCOM);
-  pinPeripheral(13, PIO_SERCOM);
-
-  // Configure DMA for SERCOM1 (our 'mySPI' port on 11/12/13)
-  Serial.println("Configuring DMA trigger");
-  myDMA.setTrigger(SERCOM1_DMAC_ID_TX);
-  myDMA.setAction(DMA_TRIGGER_ACTON_BEAT);
-
-  Serial.print("Allocating DMA channel...");
-  stat = myDMA.allocate();
-  myDMA.printStatus(stat);
-
-  desc = myDMA.addDescriptor(
-    source_memory[buffer_being_filled], // move data from here
-    (void *)(&SERCOM1->SPI.DATA.reg),   // to here
-    DATA_LENGTH,                        // this many...
-    DMA_BEAT_SIZE_BYTE,                 // bytes/hword/words
-    true,                               // increment source addr?
-    false);                             // increment dest addr?
-
-  Serial.println("Adding callback");
-  // register_callback() can optionally take a second argument
-  // (callback type), default is DMA_CALLBACK_TRANSFER_DONE
-  myDMA.setCallback(dma_callback);
-}
-
-void loop() {
-  // Fill buffer with new data.  The other buffer might
-  // still be transmitting in the background via DMA.
-  memset(source_memory[buffer_being_filled], buffer_value, DATA_LENGTH);
-
-  // Wait for prior transfer to complete before starting new one...
-  Serial.print("Waiting on prior transfer...");
-  while(!transfer_is_done) Serial.write('.');
-  mySPI.endTransaction();
-  Serial.println("Done!");
-
-  // Modify the DMA descriptor using the newly-filled buffer as source...
-  myDMA.changeDescriptor(desc,           // DMA descriptor address
-    source_memory[buffer_being_filled]); // New src; dst & count don't change
-
-  // Begin new transfer...
-  Serial.println("Starting new transfer job");
-  mySPI.beginTransaction(SPISettings(12000000, MSBFIRST, SPI_MODE0));
-  transfer_is_done = false;            // Reset 'done' flag
-  stat             = myDMA.startJob(); // Go!
-  myDMA.printStatus(stat);
-
-  // Switch buffer indices so the alternate buffer is filled/xfer'd
-  // on the next pass.
-  buffer_being_filled = 1 - buffer_being_filled;
-  buffer_value++;
-}
-
--- a/libraries/Adafruit_ZeroDMA/library.properties
+++ b/libraries/Adafruit_ZeroDMA/library.properties
@ -1,9 +0,0 @@
-name=Adafruit Zero DMA Library
-version=1.0.4
-author=Adafruit
-maintainer=Adafruit <info@adafruit.com>
-sentence=DMA helper/wrapped for ATSAMD21 such as Arduino Zero & Feather M0
-paragraph=DMA helper/wrapped for ATSAMD21 such as Arduino Zero & Feather M0
-category=Signal Input/Output
-url=https://github.com/adafruit/Adafruit_ZeroDMA
-architectures=samd
--- a/libraries/Adafruit_ZeroDMA/utility/dma.h
+++ b/libraries/Adafruit_ZeroDMA/utility/dma.h
@ -1,145 +0,0 @@
-/**
- * \file
- *
- * \brief SAM Direct Memory Access Controller Driver
- *
- * Copyright (C) 2014-2015 Atmel Corporation. All rights reserved.
- *
- * \asf_license_start
- *
- * \page License
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- * 1. Redistributions of source code must retain the above copyright notice,
- *    this list of conditions and the following disclaimer.
- *
- * 2. Redistributions in binary form must reproduce the above copyright notice,
- *    this list of conditions and the following disclaimer in the documentation
- *    and/or other materials provided with the distribution.
- *
- * 3. The name of Atmel may not be used to endorse or promote products derived
- *    from this software without specific prior written permission.
- *
- * 4. This software may only be redistributed and used in connection with an
- *    Atmel microcontroller product.
- *
- * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
- * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
- * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR
- * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
- * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
- * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- * \asf_license_stop
- *
- */
-/*
- * Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a>
- */
-#ifndef DMA_H_INCLUDED
-#define DMA_H_INCLUDED
-
-// THIS IS A PARED-DOWN VERSION OF DMA.H FROM ATMEL ASFCORE 3.
-// Please keep original copyright and license intact!
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#if (SAML21) || (SAML22) || (SAMC20) || (SAMC21) || defined(__DOXYGEN__) || defined(__SAMD51__)
-#define FEATURE_DMA_CHANNEL_STANDBY
-#endif
-
-enum dma_transfer_trigger_action{
-#ifdef __SAMD51__
-    // SAMD51 has a 'burst' transfer which can be set to one
-    // beat to accomplish same idea as SAMD21's 'beat' transfer.
-    // Trigger name is ACTON_BEAT for backward compatibility.
-    DMA_TRIGGER_ACTON_BLOCK       = DMAC_CHCTRLA_TRIGACT_BLOCK_Val,
-    DMA_TRIGGER_ACTON_BEAT        = DMAC_CHCTRLA_TRIGACT_BURST_Val,
-    DMA_TRIGGER_ACTON_TRANSACTION = DMAC_CHCTRLA_TRIGACT_TRANSACTION_Val,
-#else
-    DMA_TRIGGER_ACTON_BLOCK       = DMAC_CHCTRLB_TRIGACT_BLOCK_Val,
-    DMA_TRIGGER_ACTON_BEAT        = DMAC_CHCTRLB_TRIGACT_BEAT_Val,
-    DMA_TRIGGER_ACTON_TRANSACTION = DMAC_CHCTRLB_TRIGACT_TRANSACTION_Val,
-#endif
-};
-
-enum dma_callback_type {
-    // First item here is for any transfer errors. A transfer error is
-    // flagged if a bus error is detected during an AHB access or when
-    // the DMAC fetches an invalid descriptor
-    DMA_CALLBACK_TRANSFER_ERROR,
-    DMA_CALLBACK_TRANSFER_DONE,
-    DMA_CALLBACK_CHANNEL_SUSPEND,
-    DMA_CALLBACK_N, // Number of available callbacks
-};
-
-enum dma_beat_size {
-    DMA_BEAT_SIZE_BYTE = 0, // 8-bit
-    DMA_BEAT_SIZE_HWORD,    // 16-bit
-    DMA_BEAT_SIZE_WORD,     // 32-bit
-};
-
-enum dma_event_output_selection {
-    DMA_EVENT_OUTPUT_DISABLE = 0, // Disable event generation
-    DMA_EVENT_OUTPUT_BLOCK,       // Event strobe when block xfer complete
-    DMA_EVENT_OUTPUT_RESERVED,
-    DMA_EVENT_OUTPUT_BEAT,        // Event strobe when beat xfer complete
-};
-
-enum dma_block_action {
-    DMA_BLOCK_ACTION_NOACT = 0,
-    // Channel in normal operation and sets transfer complete interrupt
-    // flag after block transfer
-    DMA_BLOCK_ACTION_INT,
-    // Trigger channel suspend after block transfer and sets channel
-    // suspend interrupt flag once the channel is suspended
-    DMA_BLOCK_ACTION_SUSPEND,
-    // Sets transfer complete interrupt flag after a block transfer and
-    // trigger channel suspend. The channel suspend interrupt flag will
-    // be set once the channel is suspended.
-    DMA_BLOCK_ACTION_BOTH,
-};
-
-// DMA step selection. This bit determines whether the step size setting
-// is applied to source or destination address.
-enum dma_step_selection {
-    DMA_STEPSEL_DST = 0,
-    DMA_STEPSEL_SRC,
-};
-
-// Address increment step size. These bits select the address increment step
-// size. The setting apply to source or destination address, depending on
-// STEPSEL setting.
-enum dma_address_increment_stepsize {
-    DMA_ADDRESS_INCREMENT_STEP_SIZE_1 = 0, // beat size * 1
-    DMA_ADDRESS_INCREMENT_STEP_SIZE_2,     // beat size * 2
-    DMA_ADDRESS_INCREMENT_STEP_SIZE_4,     // beat size * 4
-    DMA_ADDRESS_INCREMENT_STEP_SIZE_8,     // etc...
-    DMA_ADDRESS_INCREMENT_STEP_SIZE_16,
-    DMA_ADDRESS_INCREMENT_STEP_SIZE_32,
-    DMA_ADDRESS_INCREMENT_STEP_SIZE_64,
-    DMA_ADDRESS_INCREMENT_STEP_SIZE_128,
-};
-
-// higher numbers are higher priority
-enum dma_priority {
-    DMA_PRIORITY_0, // lowest (default)
-    DMA_PRIORITY_1,
-    DMA_PRIORITY_2,
-    DMA_PRIORITY_3, // highest
-};
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif // DMA_H_INCLUDED
--- a/libraries/CI_Tests/CI_Tests.h
+++ b/libraries/CI_Tests/CI_Tests.h
@ -1 +0,0 @@
-// fake empty header file to make Arduino IDE happy
--- a/libraries/CI_Tests/examples/test_cmsis_fast_rfft/test_cmsis_fast_rfft.ino
+++ b/libraries/CI_Tests/examples/test_cmsis_fast_rfft/test_cmsis_fast_rfft.ino
@ -1,12 +0,0 @@
-#include <arm_math.h>
-
-arm_rfft_fast_instance_f32 plan;
-
-void setup() {
-  arm_rfft_fast_init_f32(&plan, 256);
-}
-
-void loop() {
-    float in[256] = { 0 }, out[256] = { 0 };
-    arm_rfft_fast_f32(&plan, in, out, 0);
-}
--- a/libraries/I2S/examples/InputSerialPlotter/.metro_m0.test.only
+++ b/libraries/I2S/examples/InputSerialPlotter/.metro_m0.test.only
--- a/libraries/I2S/examples/SimpleTone/.metro_m0.test.only
+++ b/libraries/I2S/examples/SimpleTone/.metro_m0.test.only
--- a/libraries/SDU/examples/Usage/.metro_m0.test.only
+++ b/libraries/SDU/examples/Usage/.metro_m0.test.only
--- a/libraries/SDU/extras/SDUBoot/.metro_m0.test.only
+++ b/libraries/SDU/extras/SDUBoot/.metro_m0.test.only
--- a/libraries/SDU/extras/SDUBoot/build.sh
+++ b/libraries/SDU/extras/SDUBoot/build.sh
@ -28,5 +28,4 @@ buildSDUBootSketch "arduino:samd:mkrfox1200" "$OUTPUT_PATH/mkrfox1200.h"
 buildSDUBootSketch "arduino:samd:mkrgsm1400" "$OUTPUT_PATH/mkrgsm1400.h"
 buildSDUBootSketch "arduino:samd:mkrwan1300" "$OUTPUT_PATH/mkrwan1300.h"
 buildSDUBootSketch "arduino:samd:mkrwifi1010" "$OUTPUT_PATH/mkrwifi1010.h"
-buildSDUBootSketch "arduino:samd:mkrnb1500" "$OUTPUT_PATH/mkrnb1500.h"
 buildSDUBootSketch "arduino:samd:mzero_bl" "$OUTPUT_PATH/mzero.h"
--- a/libraries/SDU/src/SDU.cpp
+++ b/libraries/SDU/src/SDU.cpp
@ -36,8 +36,6 @@ unsigned char sduBoot[0x4000] = {
  #include "boot/mkrwan1300.h"
 #elif defined(ARDUINO_SAMD_MKRWIFI1010)
  #include "boot/mkrwifi1010.h"
-#elif defined(ARDUINO_SAMD_MKRNB1500)
-  #include "boot/mkrnb1500.h"
 #elif defined(ARDUINO_SAM_ZERO)
  #include "boot/mzero.h"
 #else
--- a/libraries/SDU/src/boot/mkrnb1500.h
+++ b/libraries/SDU/src/boot/mkrnb1500.h
--- a/libraries/SPI/SPI.cpp
+++ b/libraries/SPI/SPI.cpp
@ -46,16 +46,7 @@ SPIClass::SPIClass(SERCOM *p_sercom, uint8_t uc_pinMISO, uint8_t uc_pinSCK, uint

 void SPIClass::begin()
 {
-  if(!initialized) {
-    interruptMode = SPI_IMODE_NONE;
-    interruptSave = 0;
-    interruptMask = 0;
-    initialized = true;
-  }
-
-  if(!use_dma) {
-    dmaAllocate();
-  }
+  init();

  // PIO init
  pinPeripheral(_uc_pinMiso, g_APinDescription[_uc_pinMiso].ulPinType);
@ -65,6 +56,16 @@ void SPIClass::begin()
  config(DEFAULT_SPI_SETTINGS);
 }

+void SPIClass::init()
+{
+  if (initialized)
+    return;
+  interruptMode = SPI_IMODE_NONE;
+  interruptSave = 0;
+  interruptMask = 0;
+  initialized = true;
+}
+
 void SPIClass::config(SPISettings settings)
 {
  _p_sercom->disableSPI();
@ -79,7 +80,6 @@ void SPIClass::end()
 {
  _p_sercom->resetSPI();
  initialized = false;
-  // Add DMA deallocation here
 }

 #ifndef interruptsStatus
@ -198,7 +198,7 @@ void SPIClass::setDataMode(uint8_t mode)

 void SPIClass::setClockDivider(uint8_t div)
 {
-  if(div < SPI_MIN_CLOCK_DIVIDER) {
+  if (div < SPI_MIN_CLOCK_DIVIDER) {
    _p_sercom->setBaudrateSPI(SPI_MIN_CLOCK_DIVIDER);
  } else {
    _p_sercom->setBaudrateSPI(div);
@ -235,231 +235,6 @@ void SPIClass::transfer(void *buf, size_t count)
  }
 }

-// DMA-based SPI transfer() function ---------------------------------------
-
-// IMPORTANT: references to 65535 throughout the DMA code are INTENTIONAL.
-// DO NOT try to 'fix' by changing to 65536, or large transfers will fail!
-// The BTCNT value of a DMA descriptor is an unsigned 16-bit value with a
-// max of 65535. Larger transfers are handled by linked descriptors.
-
-// Pointer to SPIClass object, one per DMA channel. This allows the
-// DMA callback (which has to exist outside the class context) to have
-// a reference back to the originating SPIClass object.
-static SPIClass *spiPtr[DMAC_CH_NUM] = { 0 }; // Legit inits list to NULL
-
-void SPIClass::dmaCallback(Adafruit_ZeroDMA *dma) {
-  // dmaCallback() receives an Adafruit_ZeroDMA object. From this we can get
-  // a channel number (0 to DMAC_CH_NUM-1, always unique per ZeroDMA object),
-  // then locate the originating SPIClass object using array lookup, setting
-  // the dma_busy element 'false' to indicate end of transfer. Doesn't matter
-  // if it's a read or write transfer...both channels get pointers to it.
-  spiPtr[dma->getChannel()]->dma_busy = false;
-}
-
-// For read-only and read+write transfers, a callback is assigned only
-// to the read channel to indicate end-of-transfer, and the write channel's
-// callback is assigned to this nonsense function (for reasons I'm not
-// entirely sure of, setting the callback to NULL doesn't work).
-static void dmaDoNothingCallback(Adafruit_ZeroDMA *dma) { (void)dma; }
-
-// This could've gone in begin(), but for the sake of organization...
-void SPIClass::dmaAllocate(void) {
-  // In order to support fully non-blocking SPI transfers, DMA descriptor
-  // lists must be created for the input and/or output data. Rather than
-  // do this dynamically with every transfer, the lists are allocated once
-  // on SPI init. Maximum list size is finite and knowable -- transfers to
-  // or from RAM or from flash memory will never exceed the corresponding
-  // memory size (if they do, you have bigger problems). Descriptors
-  // aren't large and there's usually only a handful to a dozen, so this
-  // isn't an excessive burden in exchange for big non-blocking transfers.
-  uint32_t maxWriteBytes = FLASH_SIZE; // Writes can't exceed all of flash
-#if defined(__SAMD51__)
-  uint32_t maxReadBytes = HSRAM_SIZE;  // Reads can't exceed all of RAM
-#else
-  uint32_t maxReadBytes = HMCRAMC0_SIZE;
-#endif
-  if(maxReadBytes > maxWriteBytes) { // I don't think any SAMD devices
-    maxWriteBytes = maxReadBytes;    // have RAM > flash, but just in case
-  }
-
-  // VITAL to alloc read channel first, assigns it a higher DMA priority!
-  if(readChannel.allocate() == DMA_STATUS_OK) {
-    if(writeChannel.allocate() == DMA_STATUS_OK) {
-
-      // Both DMA channels (read and write) allocated successfully,
-      // set up transfer triggers and other basics...
-
-      // readChannel callback only needs to be set up once.
-      // Unlike the write callback which may get switched on or off,
-      // read callback stays put. In certain cases the read DMA job
-      // just isn't started and the callback is a non-issue then.
-      readChannel.setTrigger(getDMAC_ID_RX());
-      readChannel.setAction(DMA_TRIGGER_ACTON_BEAT);
-      readChannel.setCallback(dmaCallback);
-      spiPtr[readChannel.getChannel()] = this;
-
-      writeChannel.setTrigger(getDMAC_ID_TX());
-      writeChannel.setAction(DMA_TRIGGER_ACTON_BEAT);
-      spiPtr[writeChannel.getChannel()] = this;
-
-      // One descriptor per channel has already been allocated
-      // in Adafruit_ZeroDMA, this just gets pointers to them...
-      firstReadDescriptor = readChannel.addDescriptor(
-        (void *)getDataRegister(), // Source address (SPI data reg)
-        NULL,                      // Dest address (set later)
-        0,                         // Count (set later)
-        DMA_BEAT_SIZE_BYTE,        // Bytes/hwords/words
-        false,                     // Don't increment source address
-        true);                     // Increment dest address
-      firstWriteDescriptor = writeChannel.addDescriptor(
-        NULL,                      // Source address (set later)
-        (void *)getDataRegister(), // Dest (SPI data register)
-        0,                         // Count (set later)
-        DMA_BEAT_SIZE_BYTE,        // Bytes/hwords/words
-        true,                      // Increment source address
-        false);                    // Don't increment dest address
-      // This is the number of EXTRA descriptors beyond the first.
-      int numReadDescriptors  = ((maxReadBytes  + 65534) / 65535) - 1;
-      int numWriteDescriptors = ((maxWriteBytes + 65534) / 65535) - 1;
-      int totalDescriptors    = numReadDescriptors + numWriteDescriptors;
-
-      if(totalDescriptors <= 0) { // Don't need extra descriptors,
-        use_dma = true;           // channels are allocated, we're good.
-      } else {                    // Else allocate extra descriptor lists...
-        // Although DMA descriptors are technically a linked list, we just
-        // allocate a chunk all at once, and finesse the pointers later.
-        if((extraReadDescriptors = (DmacDescriptor *)malloc(
-          totalDescriptors * sizeof(DmacDescriptor)))) {
-          use_dma = true; // Everything allocated successfully
-          extraWriteDescriptors = &extraReadDescriptors[numReadDescriptors];
-          // Initialize descriptors (copy from first ones)
-          for(int i=0; i<numReadDescriptors; i++) {
-            memcpy(&extraReadDescriptors[i], firstReadDescriptor,
-              sizeof(DmacDescriptor));
-          }
-          for(int i=0; i<numWriteDescriptors; i++) {
-            memcpy(&extraWriteDescriptors[i], firstWriteDescriptor,
-              sizeof(DmacDescriptor));
-          }
-        } // end malloc
-      } // end extra descriptor check
-
-      if(use_dma) { // If everything allocated successfully,
-        return;     // then we're done here.
-      }             // Otherwise clean up interim allocations...
-      writeChannel.free();
-    } // end writeChannel alloc
-    readChannel.free();
-  } // end readChannel alloc
-
-  // NOT FATAL if channel or descriptor allocation fails.
-  // transfer() function will fall back on a manual byte-by-byte loop.
-}
-
-void SPIClass::transfer(const void *txbuf, void *rxbuf, size_t count,
-  bool block) {
-
-  if((!txbuf && !rxbuf) || !count) { // Validate inputs
-    return;
-  }
-  // OK to assume now that txbuf and/or rxbuf are non-NULL, an if/else is
-  // often sufficient, don't need else-ifs for everything buffer related.
-
-  uint8_t *txbuf8 = (uint8_t *)txbuf; // Must cast to byte size
-  uint8_t *rxbuf8 = (uint8_t *)rxbuf; // for pointer math
-
-  if(use_dma) { // DMA-BASED TRANSFER YAY ----------------------------------
-
-    static const uint8_t dum = 0xFF; // Dummy byte for read-only xfers
-
-    // Set up DMA descriptor lists -----------------------------------------
-
-    DmacDescriptor *rDesc = firstReadDescriptor;
-    DmacDescriptor *wDesc = firstWriteDescriptor;
-    int descIdx = 0; // Index into extra descriptor lists
-
-    while(count) { // Counts down to end of transfer
-      uint32_t bytesThisDescriptor = count;
-      if(bytesThisDescriptor > 65535) { // Limit each descriptor
-        bytesThisDescriptor = 65535;    // to 65535 (not 65536) bytes
-      }
-      rDesc->BTCNT.reg = wDesc->BTCNT.reg = bytesThisDescriptor;
-      if(rxbuf) { // Read-only or read+write
-        // Auto-inc addresses in DMA descriptors must point to END of data.
-        // Buf pointers would advance at end of loop anyway, do it now...
-        rxbuf8 += bytesThisDescriptor;
-        rDesc->DSTADDR.reg = (uint32_t)rxbuf8;
-      }
-      if(txbuf) { // Write-only or read+write
-        txbuf8 += bytesThisDescriptor; // Same as above
-        wDesc->SRCADDR.reg       = (uint32_t)txbuf8;
-        wDesc->BTCTRL.bit.SRCINC = 1; // Increment source pointer
-      } else { // Read-only requires dummy write
-        wDesc->SRCADDR.reg       = (uint32_t)&dum;
-        wDesc->BTCTRL.bit.SRCINC = 0; // Don't increment source pointer
-      }
-      count -= bytesThisDescriptor;
-      if(count) { // Still more data?
-        // Link to next descriptors. Extra descriptors are IN ADDITION
-        // to first, so it's safe and correct that descIdx starts at 0.
-        rDesc->DESCADDR.reg = (uint32_t)&extraReadDescriptors[descIdx];
-        wDesc->DESCADDR.reg = (uint32_t)&extraWriteDescriptors[descIdx];
-        rDesc = &extraReadDescriptors[descIdx];  // Update pointers to
-        wDesc = &extraWriteDescriptors[descIdx]; // next descriptors
-        descIdx++;
-        // A write-only transfer doesn't use the read descriptor list, but
-        // it's quicker to build it (full of nonsense) anyway than to check.
-      } else { // No more data, end descriptor linked lists
-        rDesc->DESCADDR.reg = wDesc->DESCADDR.reg = 0;
-      }
-    }
-
-    // Set up DMA transfer job(s) ------------------------------------------
-
-    if(rxbuf) { // Read+write or read-only
-      // End-of-read callback is already set up, disable write CB, start job
-      writeChannel.setCallback(dmaDoNothingCallback);
-      readChannel.startJob();
-    } else { // Write-only, use end-of-write callback
-      writeChannel.setCallback(dmaCallback);
-    }
-
-    // Run DMA jobs, blocking if requested ---------------------------------
-
-    dma_busy = true;
-    writeChannel.startJob(); // All xfers, even read-only, need write job.
-    if(block) {              // If blocking transfer requested,
-      while(dma_busy);       // wait for job to finish
-    }
-
-  } else { // NON-DMA FALLBACK ---------------------------------------------
-
-    if(txbuf8) {
-      if(rxbuf8) { // Write + read simultaneously
-        while(count--) {
-          *rxbuf8++ = _p_sercom->transferDataSPI(*txbuf8++);
-        }
-      } else {     // Write only
-        while(count--) {
-          (void)_p_sercom->transferDataSPI(*txbuf8++);
-        }
-      }
-    } else {       // Read only
-      while(count--) {
-        *rxbuf8++ = _p_sercom->transferDataSPI(0xFF);
-      }
-    }
-
-  } // end non-DMA
-}
-
-// Waits for a prior in-background DMA transfer to complete.
-void SPIClass::waitForTransfer(void) {
-  while(dma_busy);
-}
-
-// End DMA-based SPI transfer() code ---------------------------------------
-
 void SPIClass::attachInterrupt() {
  // Should be enableInterrupt()
 }
@ -468,61 +243,6 @@ void SPIClass::detachInterrupt() {
  // Should be disableInterrupt()
 }

-// SPI DMA lookup works on both SAMD21 and SAMD51
-
-static const struct {
-  volatile uint32_t *data_reg;
-  int                dmac_id_tx;
-  int                dmac_id_rx;
-} sercomData[] = {
-  { &SERCOM0->SPI.DATA.reg, SERCOM0_DMAC_ID_TX, SERCOM0_DMAC_ID_RX },
-  { &SERCOM1->SPI.DATA.reg, SERCOM1_DMAC_ID_TX, SERCOM1_DMAC_ID_RX },
-  { &SERCOM2->SPI.DATA.reg, SERCOM2_DMAC_ID_TX, SERCOM2_DMAC_ID_RX },
-  { &SERCOM3->SPI.DATA.reg, SERCOM3_DMAC_ID_TX, SERCOM3_DMAC_ID_RX },
-#if defined(SERCOM4)
-  { &SERCOM4->SPI.DATA.reg, SERCOM4_DMAC_ID_TX, SERCOM4_DMAC_ID_RX },
-#endif
-#if defined(SERCOM5)
-  { &SERCOM5->SPI.DATA.reg, SERCOM5_DMAC_ID_TX, SERCOM5_DMAC_ID_RX },
-#endif
-#if defined(SERCOM6)
-  { &SERCOM6->SPI.DATA.reg, SERCOM6_DMAC_ID_TX, SERCOM6_DMAC_ID_RX },
-#endif
-#if defined(SERCOM7)
-  { &SERCOM7->SPI.DATA.reg, SERCOM7_DMAC_ID_TX, SERCOM7_DMAC_ID_RX },
-#endif
-};
-
-volatile uint32_t *SPIClass::getDataRegister(void) {
-  int8_t idx = _p_sercom->getSercomIndex();
-  return (idx >= 0) ? sercomData[idx].data_reg: NULL;
-}
-
-int SPIClass::getDMAC_ID_TX(void) {
-  int8_t idx = _p_sercom->getSercomIndex();
-  return (idx >= 0) ? sercomData[idx].dmac_id_tx : -1;
-}
-
-int SPIClass::getDMAC_ID_RX(void) {
-  int8_t idx = _p_sercom->getSercomIndex();
-  return (idx >= 0) ? sercomData[idx].dmac_id_rx : -1;
-}
-
-#if defined(__SAMD51__)
-
-// Set the SPI device's SERCOM clock CORE and SLOW clock sources.
-// SercomClockSource values are an enumeration in SERCOM.h.
-// This works on SAMD51 only.  On SAMD21, a dummy function is declared
-// in SPI.h which compiles to nothing, so user code doesn't need to check
-// and conditionally compile lines for different architectures.
-void SPIClass::setClockSource(SercomClockSource clk) {
-  int8_t idx = _p_sercom->getSercomIndex();
-  _p_sercom->setClockSource(idx, clk, true);  // true  = set core clock
-  _p_sercom->setClockSource(idx, clk, false); // false = set slow clock
-}
-
-#endif // end __SAMD51__
-
 #if SPI_INTERFACES_COUNT > 0
  /* In case new variant doesn't define these macros,
   * we put here the ones for Arduino Zero.
@ -555,3 +275,4 @@ void SPIClass::setClockSource(SercomClockSource clk) {
 #if SPI_INTERFACES_COUNT > 5
  SPIClass SPI5(&PERIPH_SPI5, PIN_SPI5_MISO, PIN_SPI5_SCK, PIN_SPI5_MOSI, PAD_SPI5_TX, PAD_SPI5_RX);
 #endif
+
--- a/libraries/SPI/SPI.h
+++ b/libraries/SPI/SPI.h
@ -21,7 +21,6 @@
 #define _SPI_H_INCLUDED

 #include <Arduino.h>
-#include <Adafruit_ZeroDMA.h>

 // SPI_HAS_TRANSACTION means SPI has
 //   - beginTransaction()
@ -38,27 +37,12 @@
 #define SPI_MODE2 0x03
 #define SPI_MODE3 0x01

-#if defined(__SAMD51__)
-  // SAMD51 has configurable MAX_SPI, else use peripheral clock default.
-  // Update: changing MAX_SPI via compiler flags is DEPRECATED, because
-  // this affects ALL SPI peripherals including some that should NOT be
-  // changed (e.g. anything using SD card). Use the setClockSource()
-  // function instead. This is left here for compatibility with interim code.
-  #if !defined(MAX_SPI)
-    #define MAX_SPI 24000000
-  #endif
-  #define SPI_MIN_CLOCK_DIVIDER 1
-#else
+#if defined(ARDUINO_ARCH_SAMD)
  // The datasheet specifies a typical SPI SCK period (tSCK) of 42 ns,
  // see "Table 36-48. SPI Timing Characteristics and Requirements",
  // which translates into a maximum SPI clock of 23.8 MHz.
-  // We'll permit use of 24 MHz SPI even though this is slightly out
-  // of spec. Given how clock dividers work, the next "sensible"
-  // threshold would be a substantial drop down to 12 MHz.
-  #if !defined(MAX_SPI)
-    #define MAX_SPI 24000000
-  #endif
-  #define SPI_MIN_CLOCK_DIVIDER (uint8_t)(1 + ((F_CPU - 1) / MAX_SPI))
+  // Conservatively, the divider is set for a 12 MHz maximum SPI clock.
+  #define SPI_MIN_CLOCK_DIVIDER (uint8_t)(1 + ((F_CPU - 1) / 12000000))
 #endif

 class SPISettings {
@ -80,11 +64,7 @@ class SPISettings {
  }

  void init_AlwaysInline(uint32_t clock, BitOrder bitOrder, uint8_t dataMode) __attribute__((__always_inline__)) {
-#if defined(__SAMD51__)
-    this->clockFreq = clock; // Clipping handled in SERCOM.cpp
-#else
-    this->clockFreq = clock >= MAX_SPI ? MAX_SPI : clock;
-#endif
+    this->clockFreq = (clock >= (F_CPU / SPI_MIN_CLOCK_DIVIDER) ? F_CPU / SPI_MIN_CLOCK_DIVIDER : clock);

    this->bitOrder = (bitOrder == MSBFIRST ? MSB_FIRST : LSB_FIRST);

@ -114,12 +94,10 @@ class SPIClass {
  public:
  SPIClass(SERCOM *p_sercom, uint8_t uc_pinMISO, uint8_t uc_pinSCK, uint8_t uc_pinMOSI, SercomSpiTXPad, SercomRXPad);

+
  byte transfer(uint8_t data);
  uint16_t transfer16(uint16_t data);
  void transfer(void *buf, size_t count);
-  void transfer(const void* txbuf, void* rxbuf, size_t count,
-         bool block = true);
-  void waitForTransfer(void);

  // Transaction Functions
  void usingInterrupt(int interruptNumber);
@ -138,21 +116,8 @@ class SPIClass {
  void setDataMode(uint8_t uc_mode);
  void setClockDivider(uint8_t uc_div);

-  // SERCOM lookup functions are available on both SAMD51 and 21.
-  volatile uint32_t *getDataRegister(void);
-  int getDMAC_ID_TX(void);
-  int getDMAC_ID_RX(void);
-  uint8_t getSercomIndex(void) { return _p_sercom->getSercomIndex(); };
-#if defined(__SAMD51__)
-  // SERCOM clock source override is available only on SAMD51.
-  void setClockSource(SercomClockSource clk);
-#else
-  // On SAMD21, this compiles to nothing, so user code doesn't need to
-  // check and conditionally compile lines for different architectures.
-  void setClockSource(SercomClockSource clk) { (void)clk; };
-#endif // end __SAMD51__
-
  private:
+  void init();
  void config(SPISettings settings);

  SERCOM *_p_sercom;
@ -167,18 +132,6 @@ class SPIClass {
  uint8_t interruptMode;
  char interruptSave;
  uint32_t interruptMask;
-
-  // transfer(txbuf, rxbuf, count, block) uses DMA when possible
-  Adafruit_ZeroDMA readChannel;
-  Adafruit_ZeroDMA writeChannel;
-  DmacDescriptor  *firstReadDescriptor   = NULL;  // List entry point
-  DmacDescriptor  *firstWriteDescriptor  = NULL;
-  DmacDescriptor  *extraReadDescriptors  = NULL;  // Add'l descriptors
-  DmacDescriptor  *extraWriteDescriptors = NULL;
-  bool             use_dma               = false; // true on successful alloc
-  volatile bool    dma_busy              = false;
-  void             dmaAllocate(void);
-  static void      dmaCallback(Adafruit_ZeroDMA *dma);
 };

 #if SPI_INTERFACES_COUNT > 0
@ -202,12 +155,14 @@ class SPIClass {

 // For compatibility with sketches designed for AVR @ 16 MHz
 // New programs should use SPI.beginTransaction to set the SPI clock
-#define SPI_CLOCK_DIV2   (MAX_SPI * 2 / 8000000)
-#define SPI_CLOCK_DIV4   (MAX_SPI * 2 / 4000000)
-#define SPI_CLOCK_DIV8   (MAX_SPI * 2 / 2000000)
-#define SPI_CLOCK_DIV16  (MAX_SPI * 2 / 1000000)
-#define SPI_CLOCK_DIV32  (MAX_SPI * 2 / 500000)
-#define SPI_CLOCK_DIV64  (MAX_SPI * 2 / 250000)
-#define SPI_CLOCK_DIV128 (MAX_SPI * 2 / 125000)
+#if F_CPU == 48000000
+  #define SPI_CLOCK_DIV2   6
+  #define SPI_CLOCK_DIV4   12
+  #define SPI_CLOCK_DIV8   24
+  #define SPI_CLOCK_DIV16  48
+  #define SPI_CLOCK_DIV32  96
+  #define SPI_CLOCK_DIV64  192
+  #define SPI_CLOCK_DIV128 255
+#endif

 #endif
--- a/libraries/Servo/README.adoc
+++ b/libraries/Servo/README.adoc
@ -1,25 +0,0 @@
-= Servo Library for Arduino =
-
-This library allows an Arduino board to control RC (hobby) servo motors.
-
-For more information about this library please visit us at
-http://www.arduino.cc/en/Reference/Servo
-
-== License ==
-
-Copyright (c) 2013 Arduino LLC. All right reserved.
-Copyright (c) 2009 Michael Margolis.  All right reserved.
-
-This library is free software; you can redistribute it and/or
-modify it under the terms of the GNU Lesser General Public
-License as published by the Free Software Foundation; either
-version 2.1 of the License, or (at your option) any later version.
-
-This library is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-Lesser General Public License for more details.
-
-You should have received a copy of the GNU Lesser General Public
-License along with this library; if not, write to the Free Software
-Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
--- a/Show more
+++ b/Show more
Author	SHA1	Message	Date
ladyada	b798c9704b	compiles & uploads	2018-09-09 19:21:47 -04:00
ladyada	6ed44b3dc4	Merge branch 'atsamr' of github.com:adafruit/ArduinoCore-samd into atsamr	2018-09-09 19:18:47 -04:00
ladyada	4871a78f0b	fix for USBcore	2018-09-09 19:13:00 -04:00
ladyada	ff6f16e1b1	variant is good to go (other than AT86RF SPI which needs special pinmuxing?)	2018-09-09 19:13:00 -04:00
ladyada	dcd707a201	SPI1 for internal Flash - tested working	2018-09-09 19:12:26 -04:00
ladyada	6536a52866	red pcb - in progress but external GPIO & uart/i2c/SPI working	2018-09-09 19:12:26 -04:00
ladyada	161d4c9ca3	rename and start making tweaks	2018-09-09 19:12:26 -04:00
ladyada	537a7e346f	fix for USBcore	2017-10-21 00:44:43 -04:00
ladyada	506d3ee57a	variant is good to go (other than AT86RF SPI which needs special pinmuxing?)	2017-10-20 15:29:17 -04:00
ladyada	1ebde085d9	SPI1 for internal Flash - tested working	2017-10-19 16:27:50 -04:00
ladyada	f707b3817b	red pcb - in progress but external GPIO & uart/i2c/SPI working	2017-10-19 16:21:59 -04:00
ladyada	0cb8512c19	rename and start making tweaks	2017-10-19 13:47:44 -04:00
				`@ -1 +0,0 @@`
				`Subproject commit e7b892095f2bb5d8bef6a748238369bdd268ed5e`
				`@ -1 +0,0 @@`
				`// fake empty header file to make Arduino IDE happy`