about GPIOTE event

[Hansome]

I'm developing a fingerprint-related project.
When the finger touches, the fingerprint sensor generates a pulse signal.
NRF52810 will triggers a GPIOTE callback, then wakeup and start BLE advertisement.

When finger touches, the problem is,
a. The oscilloscope always can display the pulse waveforms
b. But the GPIOTE callback has the probability of being locked up
c. Once locked up, the GPIOTE callback event never happen again, until reset

A lot of testing work shows that, this problem is easy to occur when UART/UARTE is used.

What I want to ask is, how to configure it to ensure that GPIOTE event will happen? Thanks!

[ovrebekk]

Hi

Can you show me the code you use to initialize the GPIOTE callback?

Is this the only pin using GPIOTE, or do you have other pins connected to the GPIOTE, such as buttons?

Best regards
Torbjørn

[Hansome]

Only one pin using GPIOTE,

static void _wakeup_pin_handler(nrf_drv_gpiote_pin_t pin, nrf_gpiote_polarity_t action)
{

	_pin_flag = true;
	
}

	
void init(void)
{
	
	nrf_drv_gpiote_in_config_t cfg = GPIOTE_CONFIG_IN_SENSE_HITOLO(false);
	
	nrf_drv_gpiote_init();
	cfg.pull = NRF_GPIO_PIN_PULLUP;
	nrf_drv_gpiote_in_init(_WAKEUP_PIN, &cfg, _wakeup_pin_handler);
	nrf_drv_gpiote_in_event_enable(_WAKEUP_PIN, true);

}	
	

void proc(void)
{

	if(_pin_flag){
		wakeup();
		_pin_flag = false;
	}
	
}

[ovrebekk]

Hi

Are you saying the event won't even happen again if the pulse signal is sent multiple times?

Are you doing a lot of processing in the UART event handler that could delay other interrupts and events?

Are you testing this on custom hardware or on a development kit?

Best regards
Torbjørn

[Hansome]

In the UART event handler, only put data to buffer,

static void _on_uart_event(app_uart_evt_t* event)
{

	uint8_t data;
	
	switch(event->evt_type){
		
		case APP_UART_DATA_READY:
			app_uart_get(&data);
			urb_push(data);
			break;

		default:
			break;
		
	}
	
}

On custom hardware

[Hansome]

In addition, How to set GPIOTE interrupt priority?

[Hansome]

In addition, what attention should be paid to its interrupt code and how to set its interrupt priority?

[ovrebekk]

Hi 

You should be able to set the GPIOTE interrupt priority by changing the GPIOTE_CONFIG_IRQ_PRIORITY define in sdk_config.h. By default it is set to 6, which is the same as the UART interrupt priority.

Maybe you can try setting it to 2 or 3 and see if it works better?

Best regards
Torbjørn