ArduinoCore-samd/cores/arduino/wiring_digital.c
2019-07-03 08:24:06 -07:00

128 lines
3.5 KiB
C

/*
Copyright (c) 2015 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
*/
#include "Arduino.h"
#ifdef __cplusplus
extern "C" {
#endif
void pinMode( uint32_t ulPin, uint32_t ulMode )
{
// Handle the case the pin isn't usable as PIO
if ( g_APinDescription[ulPin].ulPinType == PIO_NOT_A_PIN )
{
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 ;
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 ;
// Enable pull level (cf '22.6.3.2 Input Configuration' and '22.8.7 Data Output Value Set')
PORT->Group[port].OUTSET.reg = pinMask ;
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 ;
// Enable pull level (cf '22.6.3.2 Input Configuration' and '22.8.6 Data Output Value Clear')
PORT->Group[port].OUTCLR.reg = pinMask ;
break ;
case OUTPUT:
// enable input, to support reading back values, with pullups disabled
PORT->Group[port].PINCFG[pin].reg=(uint8_t)(PORT_PINCFG_INEN) ;
// Set pin to output mode
PORT->Group[port].DIRSET.reg = pinMask ;
break ;
default:
// do nothing
break ;
}
}
void digitalWrite( uint32_t ulPin, uint32_t ulVal )
{
// Handle the case the pin isn't usable as PIO
if ( g_APinDescription[ulPin].ulPinType == PIO_NOT_A_PIN )
{
return ;
}
EPortType port = g_APinDescription[ulPin].ulPort;
uint32_t pin = g_APinDescription[ulPin].ulPin;
uint32_t pinMask = (1ul << pin);
if ( (PORT->Group[port].DIRSET.reg & pinMask) == 0 ) {
// the pin is not an output, disable pull-up if val is LOW, otherwise enable pull-up
PORT->Group[port].PINCFG[pin].bit.PULLEN = ((ulVal == LOW) ? 0 : 1) ;
}
switch ( ulVal )
{
case LOW:
PORT->Group[port].OUTCLR.reg = pinMask;
break ;
default:
PORT->Group[port].OUTSET.reg = pinMask;
break ;
}
return ;
}
int digitalRead( uint32_t ulPin )
{
// Handle the case the pin isn't usable as PIO
if ( g_APinDescription[ulPin].ulPinType == PIO_NOT_A_PIN )
{
return LOW ;
}
if ( (PORT->Group[g_APinDescription[ulPin].ulPort].IN.reg & (1ul << g_APinDescription[ulPin].ulPin)) != 0 )
{
return HIGH ;
}
return LOW ;
}
#ifdef __cplusplus
}
#endif