GPIOTE Accuracy and RTC

[muon]

I'm trying to use a low accuracy GPIOTE event to start RTC1. The following code works as expected when using hi accuracy mode but will constantly trigger in_pin_handler() using low accuracy mode. If I remove nrf_drv_rtc_enable() from in_pin_handler() it functions as expected.

Is there something I'm missing either in the RTC or GPIO config?

static void gpio_init(void) {
    ret_code_t err_code;

    err_code = nrf_drv_gpiote_init();
    APP_ERROR_CHECK(err_code);

    nrf_drv_gpiote_in_config_t in_config = GPIOTE_CONFIG_IN_SENSE_HITOLO(false);
    in_config.pull = NRF_GPIO_PIN_PULLUP;

    err_code = nrf_drv_gpiote_in_init(GPIO_INPIN, &in_config, in_pin_handler);
    APP_ERROR_CHECK(err_code);

    nrf_drv_gpiote_in_event_enable(GPIO_INPIN, true);
}

static void rtc1_config(void) {
    uint32_t err_code;

    nrf_drv_rtc_config_t config = {                                                                      \
    	    .prescaler          = 1000,                                                                  \
    	    .interrupt_priority = RTC_DEFAULT_CONFIG_IRQ_PRIORITY,                                       \
    	    .reliable           = RTC_DEFAULT_CONFIG_RELIABLE,                                           \
    	    .tick_latency       = RTC_US_TO_TICKS(NRF_MAXIMUM_LATENCY_US, RTC_DEFAULT_CONFIG_FREQUENCY), \
    	};

    err_code = nrf_drv_rtc_init(&rtc1, &config, rtc1_handler);
    APP_ERROR_CHECK(err_code);
	
    nrf_drv_rtc_tick_enable(&rtc1,false);
	
	nrf_drv_rtc_counter_clear(&rtc1);

    err_code = nrf_drv_rtc_cc_set(&rtc1,0,1,true);
    APP_ERROR_CHECK(err_code);
}

void in_pin_handler(nrf_drv_gpiote_pin_t pin, nrf_gpiote_polarity_t action) {
	nrf_drv_gpiote_in_event_disable(GPIO_INPIN);
	nrf_drv_rtc_enable(&rtc1);
}

[FormerMember]

When I test what you describe, in_pin_handler()will not constantly be called. Attached is the project I have used for the testing (SDK 13): gpiote_modified.zip.

Could you test my project and check if you see the same behavior?

[muon]

Hi Kristin, thank you for your reply. I've tested your example and this works perfectly - my issue was with a pull-down within the device I have connected to the GPIO - which didn't seem to be an issue with hi accuracy mode.