watchdog.c

#include	"watchdog.h"

#ifdef USE_WATCHDOG

#include	<avr/wdt.h>
#include	<avr/interrupt.h>

#include	"arduino.h"
#include	"serial.h"

volatile uint8_t	wd_flag = 0;

// uint8_t mcusr_mirror __attribute__ ((section (".noinit")));
// void get_mcusr(void) __attribute__((naked)) __attribute__((section(".init3")));
// void get_mcusr(void) {
// 	mcusr_mirror = MCUSR;
// 	MCUSR = 0;
// 	wdt_disable();
// }

ISR(WDT_vect) {
	// watchdog has tripped- no main loop activity for 0.5s, probably a bad thing
	// if watchdog fires again, we will reset
	// perhaps we should do something more intelligent in this interrupt?
	wd_flag |= 1;
}

void wd_init() {
	// check if we were reset by the watchdog
// 	if (mcusr_mirror & MASK(WDRF))
// 		serial_writestr_P(PSTR("Watchdog Reset!\n"));

	// 0.25s timeout, interrupt and system reset
	wdt_enable(WDTO_500MS);
	WDTCSR |= MASK(WDIE);
}

void wd_reset() {
	wdt_reset();
	if (wd_flag) {
		WDTCSR |= MASK(WDIE);
		wd_flag &= ~1;
	}
}

#endif /* USE_WATCHDOG */