WTD_dummy_Test.ino

#define WDT_CONFIG_PER_3    0x3u    // 64 clock cycles
#define WDT_CONFIG_PER_4    0x4u    // 128 clock cycles
#define WDT_CONFIG_PER_5    0x5u    // 256 clock cycles
#define WDT_CONFIG_PER_6    0x6u    // 512 clock cycles
#define WDT_CONFIG_PER_7    0x7u    // 1024 clock cycles
#define WDT_CONFIG_PER_8    0x8u    // 2048 clock cycles
#define WDT_CONFIG_PER_9    0x9u    // 4096 clock cycles
#define WDT_CONFIG_PER_10   0xAu    // 8192 clock cycles
#define WDT_CONFIG_PER_11   0xBu    // 16384 clock cycles
int i=1;

void watchdog_setup(void){
  // Set up the generic clock (GCLK2) used to clock the watchdog timer at 1.024kHz
  REG_GCLK_GENDIV = GCLK_GENDIV_DIV(4) |            // Divide the 32.768kHz clock source by divisor 32, where 2^(4 + 1): 32.768kHz/32=1.024kHz
                    GCLK_GENDIV_ID(2);              // Select Generic Clock (GCLK) 2
  while (GCLK->STATUS.bit.SYNCBUSY);                // Wait for synchronization

  REG_GCLK_GENCTRL = GCLK_GENCTRL_DIVSEL |          // Set to divide by 2^(GCLK_GENDIV_DIV(4) + 1)
                     GCLK_GENCTRL_IDC |             // Set the duty cycle to 50/50 HIGH/LOW
                     GCLK_GENCTRL_GENEN |           // Enable GCLK2
                     GCLK_GENCTRL_SRC_OSCULP32K |   // Set the clock source to the ultra low power oscillator (OSCULP32K)
                     GCLK_GENCTRL_ID(2);            // Select GCLK2         
  while (GCLK->STATUS.bit.SYNCBUSY);                // Wait for synchronization

  // Feed GCLK2 to WDT (Watchdog Timer)
  REG_GCLK_CLKCTRL = GCLK_CLKCTRL_CLKEN |           // Enable GCLK2 to the WDT
                     GCLK_CLKCTRL_GEN_GCLK2 |       // Select GCLK2
                     GCLK_CLKCTRL_ID_WDT;           // Feed the GCLK2 to the WDT
  while (GCLK->STATUS.bit.SYNCBUSY);                // Wait for synchronization

  REG_WDT_CONFIG = WDT_CONFIG_PER_10;               // Set the WDT reset timeout to 16 seconds
  while(WDT->STATUS.bit.SYNCBUSY);                  // Wait for synchronization
  REG_WDT_CTRL = WDT_CTRL_ENABLE;                   // Enable the WDT in normal mode
  while(WDT->STATUS.bit.SYNCBUSY);                  // Wait for synchronization
}


void watchdog_clear(void){
  if (!WDT->STATUS.bit.SYNCBUSY)                // Check if the WDT registers are synchronized
  {
    REG_WDT_CLEAR = WDT_CLEAR_CLEAR_KEY;        // Clear the watchdog timer
    SerialUSB.println("Clear Key Sent to MCU WathcDog");
  }
}



void setup()
{
 SerialUSB.begin(9600);
 SerialUSB.println("start the i to 1");
 i=1;
 watchdog_setup();
}


void loop()
{
  i=i+1;
  delay(i*1000);
  SerialUSB.print("Delay Seconds :");
  SerialUSB.println(i);
  watchdog_clear();

}