Ticker updated to match extensions in ESP8266 API (#2849)

* Update Ticker API to compatibility with ESP8266, prepares for co-op loop Scheduler

* Fixing Build server complaints

* Fix omitted casts in template member function

* Changes after review

* Expose µs resolution of OS API in Ticker class

* Return Ticker to libraries only for modularity.

* Unify Ticker examples.

* Default for LED_BUILTIN

* In Ticker, the *scheduled functions become available in another development branch.

* Astyle from ESP8266

* Fixed Arduino keywords.txt

* 64bit integers instead of 32bits, timer functions on ESP32 accept 64bit integers.

* Move code from header into compiliation unit.

Reformat.

* Test case same as ESP8266

* Implementing inline in header saves 204+ bytes program size.

* Examples

* Fix a compiler warning due to c-style casting.

* Revert formatting changes

* More format reversions

* Revert

* Revert

* Revert

---------

Co-authored-by: Lucas Saavedra Vaz <32426024+lucasssvaz@users.noreply.github.com>

libraries/Ticker/examples/Arguments/Arguments.ino

@@ -1,51 +0,0 @@
-/*
- * This example demonstrates used of Ticker with arguments.
- * You can call the same callback function with different argument on different times.
- * Based on the argument the callback can perform different tasks.
- */
-
-#include <Arduino.h>
-#include <Ticker.h>
-
-// Arguments for the function must remain valid (not run out of scope) otherwise the function would read garbage data.
-int LED_PIN_1 = 4;
-#ifdef LED_BUILTIN
-  int LED_PIN_2 = LED_BUILTIN;
-#else
-  int LED_PIN_2 = 8;
-#endif
-
-Ticker tickerSetHigh;
-Ticker tickerSetLow;
-
-// Argument to callback must always be passed a reference
-void swapState(int *pin) {
-  static int led_1_state = 1;
-  static int led_2_state = 1;
-  if(*pin == LED_PIN_1){
-    Serial.printf("[%lu ms] set pin %d to state: %d\n", millis(), *pin, led_1_state);
-    digitalWrite(*pin, led_1_state);
-    led_1_state = led_1_state ? 0 : 1; // reverse for next pass
-  }else if(*pin == LED_PIN_2){
-    Serial.printf("[%lu ms] set pin %d to state: %d\n", millis(), *pin, led_2_state);
-    digitalWrite(*pin, led_2_state);
-    led_2_state = led_2_state ? 0 : 1; // reverse for next pass
-  }
-}
-
-void setup() {
-  Serial.begin(115200);
-  pinMode(LED_PIN_1, OUTPUT);
-  pinMode(LED_PIN_2, OUTPUT);
-  //digitalWrite(1, LOW);
-  
-  // Blink LED every 500 ms on LED_PIN_1
-  tickerSetLow.attach_ms(500, swapState, &LED_PIN_1);
-  
-  // Blink LED every 1000 ms on LED_PIN_2
-  tickerSetHigh.attach_ms(1000, swapState, &LED_PIN_2);
-}
-
-void loop() {
-
-}

libraries/Ticker/examples/TickerBasic/TickerBasic.ino

@@ -0,0 +1,49 @@
+/*
+  Basic Ticker usage
+
+  Ticker is an object that will call a given function with a certain period.
+  Each Ticker calls one function. You can have as many Tickers as you like,
+  memory being the only limitation.
+
+  A function may be attached to a ticker and detached from the ticker.
+  There are two variants of the attach function: attach and attach_ms.
+  The first one takes period in seconds, the second one in milliseconds.
+
+  The built-in LED will be blinking.
+*/
+
+#include <Ticker.h>
+
+#ifndef LED_BUILTIN
+#define LED_BUILTIN 13
+#endif
+
+Ticker flipper;
+
+int count = 0;
+
+void flip() {
+    int state = digitalRead(LED_BUILTIN);  // get the current state of GPIO1 pin
+    digitalWrite(LED_BUILTIN, !state);     // set pin to the opposite state
+
+    ++count;
+    // when the counter reaches a certain value, start blinking like crazy
+    if (count == 20) {
+        flipper.attach(0.1, flip);
+    }
+    // when the counter reaches yet another value, stop blinking
+    else if (count == 120) {
+        flipper.detach();
+    }
+}
+
+void setup() {
+    pinMode(LED_BUILTIN, OUTPUT);
+    digitalWrite(LED_BUILTIN, LOW);
+
+    // flip the pin every 0.3s
+    flipper.attach(0.3, flip);
+}
+
+void loop() {
+}

libraries/Ticker/examples/TickerParameter/TickerParameter.ino

@@ -0,0 +1,54 @@
+/*
+  Passing paramters to Ticker callbacks
+
+  Apart from void(void) functions, the Ticker library supports
+  functions taking one argument. This argument's size has to be less or
+  equal to 4 bytes (so char, short, int, float, void*, char* types will do).
+
+  This sample runs two tickers that both call one callback function,
+  but with different arguments.
+
+  The built-in LED will be pulsing.
+*/
+
+#include <Ticker.h>
+
+#ifndef LED_BUILTIN
+#define LED_BUILTIN 13
+#endif
+
+Ticker tickerSetLow;
+Ticker tickerSetHigh;
+Ticker tickerSetChar;
+
+void setPinLow() {
+    digitalWrite(LED_BUILTIN, 0);
+}
+
+void setPinHigh() {
+    digitalWrite(LED_BUILTIN, 1);
+}
+
+void setPin(int state) {
+    digitalWrite(LED_BUILTIN, state);
+}
+
+void setPinChar(char state) {
+    digitalWrite(LED_BUILTIN, state);
+}
+
+void setup() {
+    pinMode(LED_BUILTIN, OUTPUT);
+
+    // every 25 ms, call setPinLow()
+    tickerSetLow.attach_ms(25, setPinLow);
+
+    // every 26 ms, call setPinHigh()
+    tickerSetHigh.attach_ms(26, setPinHigh);
+
+    // every 54 ms, call setPinChar(1)
+    tickerSetChar.attach_ms(26, setPinChar, (char)1);
+}
+
+void loop() {
+}

libraries/Ticker/keywords.txt

@@ -10,5 +10,9 @@ Ticker	KEYWORD1
 
 attach	KEYWORD2
 attach_ms	KEYWORD2
+attach_us	KEYWORD2
 once	KEYWORD2
+once_ms	KEYWORD2
+once_us	KEYWORD2
 detach	KEYWORD2
+active	KEYWORD2

libraries/Ticker/src/Ticker.cpp

@@ -31,7 +31,7 @@ Ticker::~Ticker() {
   detach();
 }
 
-void Ticker::_attach_ms(uint32_t milliseconds, bool repeat, callback_with_arg_t callback, uint32_t arg) {
+void Ticker::_attach_us(uint64_t micros, bool repeat, callback_with_arg_t callback, void* arg) {
   esp_timer_create_args_t _timerConfig;
   _timerConfig.arg = reinterpret_cast<void*>(arg);
   _timerConfig.callback = callback;
@@ -43,9 +43,9 @@ void Ticker::_attach_ms(uint32_t milliseconds, bool repeat, callback_with_arg_t
   }
   esp_timer_create(&_timerConfig, &_timer);
   if (repeat) {
-    esp_timer_start_periodic(_timer, milliseconds * 1000ULL);
+    esp_timer_start_periodic(_timer, micros);
   } else {
-    esp_timer_start_once(_timer, milliseconds * 1000ULL);
+    esp_timer_start_once(_timer, micros);
   }
 }
 
@@ -54,10 +54,19 @@ void Ticker::detach() {
     esp_timer_stop(_timer);
     esp_timer_delete(_timer);
     _timer = nullptr;
+    _callback_function = nullptr;
   }
 }
 
-bool Ticker::active() {
+bool Ticker::active() const {
   if (!_timer) return false;
   return esp_timer_is_active(_timer);
 }
+
+void Ticker::_static_callback(void* arg)
+{
+  Ticker* _this = reinterpret_cast<Ticker*>(arg);
+  if (_this && _this->_callback_function)
+    _this->_callback_function();
+}
+

libraries/Ticker/src/Ticker.h

@@ -28,79 +28,110 @@
 extern "C" {
   #include "esp_timer.h"
 }
+#include <functional>
 
 class Ticker
 {
 public:
   Ticker();
   ~Ticker();
-  typedef void (*callback_t)(void);
-  typedef void (*callback_with_arg_t)(void*);
 
-  void attach(float seconds, callback_t callback)
+  typedef void (*callback_with_arg_t)(void*);
+  typedef std::function<void(void)> callback_function_t;
+
+  void attach(float seconds, callback_function_t callback)
   {
-    _attach_ms(seconds * 1000, true, reinterpret_cast<callback_with_arg_t>(callback), 0);
+    _callback_function = std::move(callback);
+    _attach_us(1000000ULL * seconds, true, _static_callback, this);
   }
 
-  void attach_ms(uint32_t milliseconds, callback_t callback)
+  void attach_ms(uint64_t milliseconds, callback_function_t callback)
   {
-    _attach_ms(milliseconds, true, reinterpret_cast<callback_with_arg_t>(callback), 0);
+    _callback_function = std::move(callback);
+    _attach_us(1000ULL * milliseconds, true, _static_callback, this);
+  }
+
+  void attach_us(uint64_t micros, callback_function_t callback)
+  {
+    _callback_function = std::move(callback);
+    _attach_us(micros, true, _static_callback, this);
   }
 
   template<typename TArg>
   void attach(float seconds, void (*callback)(TArg), TArg arg)
   {
-    static_assert(sizeof(TArg) <= sizeof(uint32_t), "attach() callback argument size must be <= 4 bytes");
+    static_assert(sizeof(TArg) <= sizeof(void*), "attach() callback argument size must be <= sizeof(void*)");
     // C-cast serves two purposes:
     // static_cast for smaller integer types,
     // reinterpret_cast + const_cast for pointer types
-    uint32_t arg32 = (uint32_t)arg;
-    _attach_ms(seconds * 1000, true, reinterpret_cast<callback_with_arg_t>(callback), arg32);
+    _attach_us(1000000ULL * seconds, true, reinterpret_cast<callback_with_arg_t>(callback), reinterpret_cast<void*>(arg));
   }
 
   template<typename TArg>
-  void attach_ms(uint32_t milliseconds, void (*callback)(TArg), TArg arg)
+  void attach_ms(uint64_t milliseconds, void (*callback)(TArg), TArg arg)
   {
-    static_assert(sizeof(TArg) <= sizeof(uint32_t), "attach_ms() callback argument size must be <= 4 bytes");
-    uint32_t arg32 = (uint32_t)arg;
-    _attach_ms(milliseconds, true, reinterpret_cast<callback_with_arg_t>(callback), arg32);
+    static_assert(sizeof(TArg) <= sizeof(void*), "attach() callback argument size must be <= sizeof(void*)");
+    _attach_us(1000ULL * milliseconds, true, reinterpret_cast<callback_with_arg_t>(callback), reinterpret_cast<void*>(arg));
   }
 
-  void once(float seconds, callback_t callback)
+  template<typename TArg>
+  void attach_us(uint64_t micros, void (*callback)(TArg), TArg arg)
   {
-    _attach_ms(seconds * 1000, false, reinterpret_cast<callback_with_arg_t>(callback), 0);
+    static_assert(sizeof(TArg) <= sizeof(void*), "attach() callback argument size must be <= sizeof(void*)");
+    _attach_us(micros, true, reinterpret_cast<callback_with_arg_t>(callback), reinterpret_cast<void*>(arg));
   }
 
-  void once_ms(uint32_t milliseconds, callback_t callback)
+  void once(float seconds, callback_function_t callback)
   {
-    _attach_ms(milliseconds, false, reinterpret_cast<callback_with_arg_t>(callback), 0);	
+    _callback_function = std::move(callback);
+    _attach_us(1000000ULL * seconds, false, _static_callback, this);
+  }
+
+  void once_ms(uint64_t milliseconds, callback_function_t callback)
+  {
+    _callback_function = std::move(callback);
+    _attach_us(1000ULL * milliseconds, false, _static_callback, this);
+  }
+
+  void once_us(uint64_t micros, callback_function_t callback)
+  {
+    _callback_function = std::move(callback);
+    _attach_us(micros, false, _static_callback, this);
   }
 
   template<typename TArg>
   void once(float seconds, void (*callback)(TArg), TArg arg)
   {
-    static_assert(sizeof(TArg) <= sizeof(uint32_t), "attach() callback argument size must be <= 4 bytes");
-    uint32_t arg32 = (uint32_t)(arg);
-    _attach_ms(seconds * 1000, false, reinterpret_cast<callback_with_arg_t>(callback), arg32);
+    static_assert(sizeof(TArg) <= sizeof(void*), "attach() callback argument size must be <= sizeof(void*)");
+    _attach_us(1000000ULL * seconds, false, reinterpret_cast<callback_with_arg_t>(callback), reinterpret_cast<void*>(arg));
   }
 
   template<typename TArg>
-  void once_ms(uint32_t milliseconds, void (*callback)(TArg), TArg arg)
+  void once_ms(uint64_t milliseconds, void (*callback)(TArg), TArg arg)
   {
-    static_assert(sizeof(TArg) <= sizeof(uint32_t), "attach_ms() callback argument size must be <= 4 bytes");
-    uint32_t arg32 = (uint32_t)(arg);
-    _attach_ms(milliseconds, false, reinterpret_cast<callback_with_arg_t>(callback), arg32);
+    static_assert(sizeof(TArg) <= sizeof(void*), "attach() callback argument size must be <= sizeof(void*)");
+    _attach_us(1000ULL * milliseconds, false, reinterpret_cast<callback_with_arg_t>(callback), reinterpret_cast<void*>(arg));
+  }
+
+  template<typename TArg>
+  void once_us(uint64_t micros, void (*callback)(TArg), TArg arg)
+  {
+    static_assert(sizeof(TArg) <= sizeof(void*), "attach() callback argument size must be <= sizeof(void*)");
+    _attach_us(micros, false, reinterpret_cast<callback_with_arg_t>(callback), reinterpret_cast<void*>(arg));
   }
 
   void detach();
-  bool active();
+  bool active() const;
 
 protected:	
-  void _attach_ms(uint32_t milliseconds, bool repeat, callback_with_arg_t callback, uint32_t arg);
+  static void _static_callback(void* arg);
 
+  callback_function_t _callback_function = nullptr;
 
-protected:
   esp_timer_handle_t _timer;
+
+private:
+  void _attach_us(uint64_t micros, bool repeat, callback_with_arg_t callback, void* arg);
 };