Watchdog Timer

The watchdog timer is a very useful feature for projects that are intended to run for extended periods of time or contain unstable loops of code. The watchdog is essentially a small timer that will force a full system restart if the timer is not updated within a preset time. For more information and APIs about memory status, please visit MbedOS.

Assembly

Arduino.h

Summary

Constructor

Watchdog

Watchdog()

Constructor of Watchdog class

Methods

configure

bool configure(float timeoutInMs)

Configure Watchdog timer with reset interval.

Parameters

Type	Name	Description
float	timeoutInMs	timeout interval in milliseconds, as a float

Return value

Returns true if the Watchdog is configured successfully, false for invalid input.

resetTimer

void resetTimer()

Reset Watchdog timer to prevent it from a system reset.

Parameters

None

Return value

None

resetTriggered

bool resetTriggered()

Get the flag to indicate if the Watchdog trigger a system reset.

Parameters

None

Return value

Returns true if the Watchdog reset is triggered, else return false.

Sample code

#include "Arduino.h"

Watchdog watchdog;

void setup() {
  // setup a 10 second timeout on watchdog timer hardware
  bool ret = watchdog.configure(10000);
  if (!ret)
  {
    Serial.println("Configure watchdog failed.");
  }
}

void loop() {
  // Main program loop - reset watchdog timer to prevent a system reset
  watchdog.resetTimer();
  
  // Do other work
  Serial.println("loop");
  delay(1000);
}