wdt-feed

Open the watchdog, feed it on a cadence, observe a reset when feeding stops. The minimal demo for <alp/wdt.h>.

Source: examples/wdt-feed/.

board.yaml

schema_version: 2

som:
  sku: E1M-AEN701

carrier:
  name: E1M-EVK

cores:
  m55_hp:
    os: zephyr
    app: ./src
    peripherals: [wdt]

diagnostics:
  log_level: info

Source (abbreviated)

#include <alp/wdt.h>

int main(void) {
    alp_wdt_t *wdt = alp_wdt_open(&(alp_wdt_config_t){
        .timeout_ms = 2000,
    });
    if (wdt == NULL) return -1;

    alp_wdt_start(wdt);
    for (int i = 0; i < 5; i++) {
        printk("[wdt] feed %d/5\n", i);
        alp_wdt_feed(wdt);
        k_msleep(1500);   /* 1.5 s < 2 s timeout, safe */
    }

    printk("[wdt] stopping feed; expecting reset in ~2 s\n");
    k_msleep(5000);       /* watchdog fires here */
    return 0;
}

Expected behaviour

Five feeds, then the device resets ~2 s after the last feed. Re-boots into the same example, which logs the reset cause from alp_wdt_last_reset_was_watchdog().

See also

• <alp/wdt.h> reference
• Examples overview