hwa/atmel/avr/examples/02-1-blink-watchdog-stat/main.c

Blink a LED using the watchdog flag

This program configures the LED pin as a digital output and the watchdog to trigger an IRQ periodically. Then, in an infinite loop, when the watchdog IRQ flag is set, it clears it and toggles the LED state.

A HWA context is used to gather the configuration and write it into the hardware registers at once with the most efficient code possible.

 
/*  This file is part of the HWA project.
 *  Copyright (c) 2012,2015 Christophe Duparquet.
 *  All rights reserved. Read LICENSE.TXT for details.
 */
 
#include BOARD_H
 
 
int main ( )
{
  /*  Create a HWA context to collect the hardware configuration
   *  Preload this context with RESET values
   */
  hwa( begin, reset );
 
  /*  Configure the LED pin
   */
  hwa( configure, PIN_LED, mode, digital_output );
 
  /*  Configure the watchdog to trigger an IRQ periodically
   */
  hwa( configure, watchdog0,
       timeout,   250ms,
       action,    irq       );
 
  //  hwa( write, (portb,1,4), 2 );
 
  /*  Write this configuration into the hardware
   */
  hwa( commit );
 
  for(;;) {
    /*
     *  As soon as the watchdog IRQ flag is set, clear
     *  it and toggle the LED.
     */
    if ( hw( read, (watchdog0,irq) ) ) {
      hw( clear, (watchdog0,irq) );
      hw( toggle, PIN_LED );
    }
  }
    
  return 0 ;
}