avr-firmwares/drivers/led.c

#include "led.h"
#include <avr/io.h>

void __attribute__ ((naked)) __attribute__ ((section (".init5"))) led_init() {
	LED_DDR |= (1 << LED_PIN);
}

void led(uint8_t on) {
	if (on) {
		LED_PORT |= (1 << LED_PIN);
	} else {
		LED_PORT &= ~(1 << LED_PIN);
	}
}