/** * Copyright (c) 2020 Raspberry Pi (Trading) Ltd. * * SPDX-License-Identifier: BSD-3-Clause */ #include <stdio.h> #include "pico/stdlib.h" /// \tag::timer_example[] volatile bool timer_fired = false; int64_t alarm_callback(alarm_id_t id, __unused 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(__unused 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; } /// \end::timer_example[]

This firmware image was imported from the pico-examples repository. 


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