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
45
46
47
48
49
50
51
52
|
/*
* Example code for multicore example with python interface
*/
#include <avr/interrupt.h>
#ifdef DUAL_B
// Code for core B: count events on port B2
volatile char cnt_irq = 0; // IRQ counter
volatile char cnt_res = 0; // measurement value for time distance between events
ISR(INT0_vect) {
cnt_irq++; // increment event counter
cnt_res = TCNT0; // save timer value = time distance to last event
TCNT0 = 0; // reset timer value
}
void init() {
MCUCR = _BV(ISC00) | _BV(ISC01); // rising edge will generate interrupt
GICR |= _BV(INT0); // enable INT0
GIFR |= _BV(INTF0); // reset former irq request
TCNT0 = 0; // Timer 0 as counter with internal clock
TCCR0 = 0x0 + 0x04 + 0x0; // wgm=0, cs=4, com=0
sei(); // enable interrupts
}
#endif
#ifdef DUAL_A
// Code for core A: generate 250Hz signal on port B3
void init() {
TCNT0 = 0; // reset timer
OCR0 = 124; // Timer 0 by CLK/64, 2ms on 4MHz, CTC mode,
// 4ms period on OC0 out
TCCR0 = 0x08 + 0x03 + 0x10; // wgm=2, cs=3, com=1
DDRB = 0x8; // PB3=out
}
#endif
// Mainloop
int main() {
init();
for(;;);
return 0;
}
// EOF
|
