#include<avr/wdt.h> /* Header for watchdog timers in AVR */

void setup() {
    Serial.begin(9600); /* Define baud rate for serial communication */
    Serial.println("Watchdog Demo Starting");
    pinMode(13, OUTPUT);
    wdt_disable();  /* Disable the watchdog and wait for more than 2 seconds */
    delay(3000);  /* Done so that the Arduino doesn't keep resetting infinitely in case of wrong configuration */
    wdt_enable(WDTO_2S);  /* Enable the watchdog with a timeout of 2 seconds */
}

void loop() {
    for (int i = 0; i<20; i++) /* Blink LED for some time */
    {
        digitalWrite(13, HIGH);
        delay(100);
        digitalWrite(13, LOW);
        delay(100);
        wdt_reset();  /* Reset the watchdog */
    }
    while (1); /* Infinite loop. Will cause watchdog timeout and system reset. */
}

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