General • Re: Reading gpio returns incorrect value

Code:

#include <stdlib.h>#include <stdio.h>#include <string.h>#include "pico/stdlib.h"#include "pico/time.h"#define GPIO2   2#define GPIO15  15int main() {        unsigned long count = 0;        int in, out = 0;        stdio_init_all();        gpio_init(GPIO2);        gpio_init(GPIO15);        gpio_set_dir(GPIO2, GPIO_OUT);        gpio_set_dir(GPIO15, GPIO_IN);        while (1) {                gpio_put(GPIO2, out);                printf("[%016lu] set GPIO2 to %d\n", to_ms_since_boot(get_absolute_time()), out);                count = 0;                while ((in = gpio_get(GPIO15)) != out)                        count++;                printf("[%016lu] got GPIO15 to %d, count = %lu\n", to_ms_since_boot(get_absolute_time()), out, count);                out = !out;                sleep_ms(1000);        }        return 0;}

Code:

[0000000000052377] set GPIO2 to 0[0000000000052380] got GPIO15 to 0, count = 0[0000000000053384] set GPIO2 to 1[0000000000053387] got GPIO15 to 1, count = 0