// https://raspberrypi.github.io/pico-sdk-doxygen/group__hardware__timer.html#timer_example
#include <stdio.h>
#include "pico/stdlib.h"
volatile bool timer_fired = false;
int64_t alarm_callback(alarm_id_t id, void *user_data) {
printf("Timer %d fired!\n", (int) id);
timer_fired = true;
// Can return a value here in us to fire in the future
return 0;
}
bool repeating_timer_callback(struct repeating_timer *t) {
printf("Repeat at %lld\n", time_us_64());
return true;
}
int main() {
stdio_init_all();
printf("Hello Timer!\n");
// Call alarm_callback in 2 seconds
add_alarm_in_ms(2000, alarm_callback, NULL, false);
// Wait for alarm callback to set timer_fired
while (!timer_fired) {
tight_loop_contents();
}
// Create a repeating timer that calls repeating_timer_callback.
// If the delay is > 0 then this is the delay between the previous callback ending and the next starting.
// If the delay is negative (see below) then the next call to the callback will be exactly 500ms after the
// start of the call to the last callback
struct repeating_timer timer;
add_repeating_timer_ms(500, repeating_timer_callback, NULL, &timer);
sleep_ms(3000);
bool cancelled = cancel_repeating_timer(&timer);
printf("cancelled... %d\n", cancelled);
sleep_ms(2000);
// Negative delay so means we will call repeating_timer_callback, and call it again
// 500ms later regardless of how long the callback took to execute
add_repeating_timer_ms(-500, repeating_timer_callback, NULL, &timer);
sleep_ms(3000);
cancelled = cancel_repeating_timer(&timer);
printf("cancelled... %d\n", cancelled);
sleep_ms(2000);
printf("Done\n");
return 0;
}