door_lock/main.c


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44

#include <stddef.h>
#include <avr/io.h>
#include <util/delay.h>

#include "serial.h"

#define PWM_MIN 1200
#define PWM_MID 3000
#define PWM_MAX 5000

#define SERVO_PIN  PB1
#define LOCK_BTN   PD6
#define UNLOCK_BTN PD7

static inline void servo_init(void)
{
	DDRB |= 1 << SERVO_PIN;
	TCCR1A |= (1 << WGM11) | (1 << COM1A1);
	TCCR1B |= (1 << WGM12) | (1 << WGM13) | (1 << CS11);
	ICR1 = 40000;

	DDRD &= ~((1 << LOCK_BTN) | (1 << UNLOCK_BTN));
	PORTD |= (1 << LOCK_BTN) | (1 << UNLOCK_BTN);
}

static inline uint8_t is_btn_pressed(uint8_t btn)
{
	return !((PIND >> btn) & 0x01);
}

int main(void) 
{
	servo_init();

	for(;;) {
		if (is_btn_pressed(LOCK_BTN))
			OCR1A = PWM_MID;

		if (is_btn_pressed(UNLOCK_BTN))
			OCR1A = PWM_MIN;
	}

	return 0;
}