72 lines
1.4 KiB
C
72 lines
1.4 KiB
C
|
|
||
|
|
#include <stdint.h>
|
||
|
|
#include <avr/interrupt.h>
|
||
|
|
#include <avr/common.h>
|
||
|
|
#include <avr/io.h>
|
||
|
|
#include "util.h"
|
||
|
|
|
||
|
|
static volatile uint8_t internal_counter;
|
||
|
|
|
||
|
|
void timer_init(void)
|
||
|
|
{
|
||
|
|
/* initialize timer2, CTC at 10ms, prescaler 1024 */
|
||
|
|
OCR2A = F_CPU/1024/100;
|
||
|
|
TCCR2A = _BV(WGM21);
|
||
|
|
TCCR2B = _BV(CS22) | _BV(CS21) | _BV(CS20);
|
||
|
|
TIMSK2 = _BV(OCIE2A);
|
||
|
|
}
|
||
|
|
|
||
|
|
void timer_set(timer_t *t, uint8_t timeout)
|
||
|
|
{
|
||
|
|
t->current = internal_counter;
|
||
|
|
t->timeout = timeout;
|
||
|
|
}
|
||
|
|
|
||
|
|
void timerL_set(timerL_t *t, uint16_t timeout)
|
||
|
|
{
|
||
|
|
t->current = internal_counter;
|
||
|
|
t->timeout = timeout;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
bool timer_expired(timer_t *t)
|
||
|
|
{
|
||
|
|
if (t->timeout == 0)
|
||
|
|
return true;
|
||
|
|
|
||
|
|
/* attention: may fail if internal counter is incremented by more than one
|
||
|
|
* between two calls of timer_expired()! (that is if its is called less than every 10ms*/
|
||
|
|
if (t->current != internal_counter) {
|
||
|
|
t->timeout--;
|
||
|
|
t->current = internal_counter;
|
||
|
|
}
|
||
|
|
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
bool timerL_expired(timerL_t *t)
|
||
|
|
{
|
||
|
|
if (t->timeout == 0)
|
||
|
|
return true;
|
||
|
|
|
||
|
|
/* attention: may fail if internal counter is incremented by more than one
|
||
|
|
* between two calls of timer_expired()! */
|
||
|
|
if (t->current != internal_counter) {
|
||
|
|
t->timeout--;
|
||
|
|
t->current = internal_counter;
|
||
|
|
}
|
||
|
|
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
/* timer interrupt function */
|
||
|
|
ISR(TIMER2_COMPA_vect, ISR_NOBLOCK) {
|
||
|
|
internal_counter++;
|
||
|
|
}
|
||
|
|
|