webradio/firmware/pm.c

#include <avr/io.h>
#include <avr/sleep.h>
#include <util/delay.h>
#include <avr/interrupt.h>
#include <avr/pgmspace.h>
#include "pm.h"
#include "batmon.h"

static void disable_periphery()
{
	cli();
	WDTCSR = 0;
	TWCR = 0;
	SPCR = 0;
	ADCSRA = 0;
	DDRB = 0;
	DDRC = 0;
	DDRD = 0;
	PORTB = 0;
	PORTC = 0;
	PORTD = (1 << 2); // Pullup for INT0
}

void suspend()
{
	disable_periphery();

	EICRA = 0;
	EIMSK = (1 << INT0);
	SMCR = (1 << SM1) | (1 << SE);
	sei();
	sleep_cpu();
	cli();

	_delay_ms(50);
	while (!(PIND & (1 << 2)));
	_delay_ms(50);
}

ISR(INT0_vect)
{
	return;
}

void reset()
{
	disable_periphery();
	// WDTCSR = (1 << WDE) | (1 << WDP2);
	// For some reason, the WD reset locks up my chip,
	// so let's just jump to the reset vector directly.
	asm("ldi R16,0x00");
	asm("push R16");
	asm("push R16");
	asm("push R16");
	asm("push R16");
	asm("ret");
	while (1);
}

char* post()
{
	_delay_ms(500);

	if (!batmon_ok_to_boot())
		return PSTR("Low battery.");

	return 0;
}