watchdog timer

[Bret Foreman]

Is there an app-note, tutorial, or example of how to use the watchdog timer to reset the MCU if the application hangs?

[Hans-Christian Otto]

Sorry but this doesnt work, too. I use this steps:

lfclk_config(); CRV = (32768) - 1;
NRF_WDT->RREN = (WDT_RREN_RR0_Enabled INTENSET = 1;
NVIC_EnableIRQ(WDT_IRQn);
NVIC_SetPriority(WDT_IRQn,0);

in the ISR I pull down the enable pin from my 3V LDO to power off the uC.

[Hans-Christian Otto]

Ah now it works, the problem was: At the beginning I set the 3V_enable_switch to on. After the WDT reset+pull down the 3V_enable_switch the uC reset very fast and have enough power to reach the row with the 3V_enable_switch command.

[Gil DePaula]

Hi Ole,

I tried the code below, but it doesn't work. It does not go to the handler, and it doesn't reset either. I closed the debugger and did a power cycle as required. In the handler, all I do is turn the LED on (LED function works with a button press, for example). I'm not reloading it anywhere yet either. What am I doing wrong?

void watchdog_init(void) { NRF_WDT->CONFIG = (WDT_CONFIG_HALT_Pause << WDT_CONFIG_HALT_Pos) | (WDT_CONFIG_SLEEP_Pause << WDT_CONFIG_SLEEP_Pos);

NRF_WDT->CRV = (32768 * 1); // Timeout period of 1 s

NRF_WDT->RREN |= WDT_RREN_RR0_Msk; //Enable reload register 0

NRF_WDT->INTENSET = WDT_INTENSET_TIMEOUT_Msk;

NVIC_ClearPendingIRQ(WDT_IRQn); NVIC_SetPriority(WDT_IRQn, APP_IRQ_PRIORITY_HIGH); NVIC_EnableIRQ(WDT_IRQn);

NRF_WDT->TASKS_START = 1; // Watchdog start }

Thank you!

Gil

[Sébastien Despont]

Hi,

If you are using the soft device, you cannot set the priority level as high which is reserved in this case. Try to set it to low priority.

[Bastiaan]

Thank you Sébastien, Unfortunately it still does not work. I tried it with this: NVIC_SetPriority(WDT_IRQn, APP_IRQ_PRIORITY_LOW); Regards, Gil