Using app_timer callback

[Andrei]

Hello, I'm trying to do a millisecond counter using app_timer but the callback is never called. I think I have missunderstood how it works. I've tried using the app_timer with or without softdevice, in debug mode and without debug mode, but still the timeout handler is not called.

What am I doing wrong?

Thank you.

My code is as follows:

static void timeout_handler(void * p_context)
{
    //UNUSED_PARAMETER(p_context);
    //battery_start();

    simple_uart_putstring((const uint8_t *)"time!\n\r");
    millis+=20;
}

int main(void)
{
simple_uart_config(RTS_PIN_NUMBER, TX_PIN_NUMBER, CTS_PIN_NUMBER, RX_PIN_NUMBER, HWFC);
simple_uart_putstring((const uint8_t *)"Start using device \n\r");

APP_TIMER_INIT(0, 4, 5, false);

  NRF_CLOCK->TASKS_LFCLKSTART = 1;

    	while (NRF_CLOCK->EVENTS_LFCLKSTARTED == 0);
    	NRF_CLOCK->EVENTS_LFCLKSTARTED = 0;

      
      NRF_CLOCK->TASKS_LFCLKSTART = 1;

      while (NRF_CLOCK->EVENTS_LFCLKSTARTED == 0);

        // Create timer
      err_code = app_timer_create(&test_timer_id, APP_TIMER_MODE_REPEATED, timeout_handler);
      APP_ERROR_CHECK(err_code);

      err_code =app_timer_start(test_timer_id, 100, NULL);
      APP_ERROR_CHECK(err_code);

uint8_t sd_is_enabled;
while (true)
{

	    (void)sd_softdevice_is_enabled(&sd_is_enabled);
	    if (sd_is_enabled)
	    {
	        uint32_t err_code = sd_app_event_wait();
	        APP_ERROR_CHECK(err_code);
	    }
	    else
	        __WFI()
}

}

[cocoa]

This code is tested on EK board with soft device, the callback from timer is called every 500 ms.

#define LED0	 18
#define LED1	 19
#define BTN0	 16
#define BTN1	 17

#define PRESCALER				0
#define MAX_TIMERS			1
#define OP_QUEUES_SIZE	4
#define USE_SCHEDULER		false

#define TIMER_MS				500
#define TIMER_TICKS			APP_TIMER_TICKS(TIMER_MS, PRESCALER)



// alloc timer object

static app_timer_id_t			 testTimer;



static void powerManager(void)
{
	 uint32_t error_code;
	 error_code = sd_app_event_wait();
	 APP_ERROR_CHECK(error_code);
}

// Timer callback
static void timerDidEnd(void *nil)
{
	 // blink to say Hello!!
	 nrf_gpio_pin_toggle(LED0);
	 nrf_gpio_pin_toggle(LED1);
}


static void bleEventManager(ble_evt_t *stackEvent)
{
	 // stack event received
	 // do nothing
	 switch (stackEvent->header.evt_id)
	{
		 default:
			break;
	}
}


int main (void)
{
	 uint32_t errorCode;
	 
	 // I'm alive, led0 on
	 GPIO_LED_CONFIG(LED0);
	 GPIO_LED_CONFIG(LED1);
	 nrf_gpio_pin_set(LED0);
	 
	 
	 // stack init
	 BLE_STACK_HANDLER_INIT(NRF_CLOCK_LFCLKSRC_XTAL_20_PPM,
													BLE_L2CAP_MTU_DEF,
													bleEventManager,
													false);

	 // init timer module
	 APP_TIMER_INIT(PRESCALER, MAX_TIMERS, OP_QUEUES_SIZE, USE_SCHEDULER);
	 
	 // create a timer
	 errorCode = app_timer_create(&testTimer,
																 APP_TIMER_MODE_REPEATED,
																 timerDidEnd);
	 
	 APP_ERROR_CHECK(errorCode);
	 
	 // timer starts,
	 errorCode = app_timer_start(testTimer,
																TIMER_TICKS,
																NULL);
	 APP_ERROR_CHECK(errorCode);
	 
	 
	 for(;;)
		 {
			 powerManager();
	   }
	 
	 
}

-c

[Andrei]

Hello, Thanks for the answer, I've tried using the example you provided but it still doesn't work. When used in debug with eclipse it crashes at BLE_STACK_HANDLER_INIT with error 8194 which I checked and seems to be NRF_ERROR_SOFTDEVICE_NOT_ENABLED. When I tried it without the debugger the LED0 lights up when entering main but still doesn't blink afterwards (neither does LED1).

I'm using nrf51822 EK with eclipse, softdevice firmware 5.2.1. Have you used another configuration for the tests or maybe there is a compilation problem?

Andrei

[bg2bkk]

thank you, it can be applied on my project directly. I have no other configurations.