WatchdogTimer Library for Arduino Zero: WDTZero

Components and supplies

Arduino MKR WiFi 1010

About this project

WDTZero.h - Library for Watchdog on the SAM D Zero Series

See ATSAMD2x datasheet, #18, page205 onwards

Defines Watchdog Calss to Setup Watchdog timer in Normal mode with EarlyWarning interrupt.

1. Sets Hardware WDT timer

-> for stalled processor situations, generates a reset
-> 4, 8 or 16 seconds response

2. Sets Software WDT using EarlyWarning timer (EWT) and software counter (Global Variable)

-> for stalled software, generates a reset if software loop does not clear WDT on time
-> EWT runs on 0.5 Sec interval ISR
-> Total soft-WDT intervals are 4, 8, 6, 32 Seconds, 1, 2, 4, 10 Minutes

Code

WDTZero DemoC/C++

Arduini sketch

#include <WDTZero.h>

byte wdtCounter, wdtCounterReset;
WDTZero MyWatchDoggy(WDT_HARDCYCLE4S); // Define WDT with hard-Watchdog @ 4 seconds - hardstop when processor is stalled. Configure your soft-counter at .Setup(). 

void setup() {
  int t = 20; //Initialize serial and wait for port to open, max 10 seconds
  Serial.begin(9600);
  while (!Serial) {
    delay(500);
    if ( (t--) == 0 ) break;
  }
 Serial.print("\nWDTZero-Demo : Setup Watchdog at 16Sec interval"); 
 MyWatchDoggy.setup(WDT_CYCLE16S);  // initialize WDT-softcounter refesh cycle on 16sec interval
}

void loop() {
  unsigned int t = 0;


  Serial.print("\nWatchdog Test1 - loop 30 seconds with a WDT.clear()\n");
  for (t = 1; t < 30; ++t) {
    MyWatchDoggy.clear();  // refresh wdt - before it loops
    delay(950);
    Serial.print(t);Serial.print(".");
  }

  Serial.print("\n\nWatchdog Test2 - Free run wait for reset\n");
  for (t = 1; t < 30; ++t) {
    delay(950);
    Serial.print(t);Serial.print(".");
    }
    
Serial.print("\nYou will never read this line");

}