wdt.c


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static uint8_t wdt_generation __attribute__((section (".noinit")));

static void wdt_init(void)
{
	uint8_t temp;
	/* timed sequence. bit 4: WDCE, bit 3: WDE,
	 * 0x07 = WDP2 | WDP1 | WDP0 = 2s */
	asm volatile ("\n\
WDTCSR	= 0x60\n\
WDCE	= 4\n\
WDE	= 3\n\
		wdr	\n\
			\n\
		ldi	%[temp], (1 << WDCE) | (1 << WDE)	\n\
		sts	WDTCSR, %[temp]				\n\
			\n\
		ldi	%[temp], (1 << WDE) | 0x20		\n\
		sts	WDTCSR, %[temp]				\n\
	" : [temp] "=r" (temp) :  : "memory");

	if (MCUSR & (1 << WDRF))
		wdt_generation++;
}