NRF51822 Interrupt Service Routine handling

[Krzysiek]

Hello, I was using wiringPiSPI() to connect via SPI and so i was using wiringPiISR function to create an interupt handler that will do callback to the user suplied function. Now I moved to module with NRF architecture. How can I handle interuptions the way i was doing it on the Raspberry PI? I'm using spi_master.h to connect via SPI. Is there any ready to use ISR handle the way it was made on Raspberry?

[Krzysiek]

Comment field is a little to small so I will paste it here as a new post.

I started to use GPIOTE and managed to sucesfully get interupt from external device. Next problem I have is, that when IRQHandler kicks in, whole system freezes (with APP_IRQ_PRIORITY_HIGH) or program isn't executed correctly (with APP_IRQ_PRIORITY_LOW)

isr() function read and write to device through SPI (And here I'm not so sure what happens with concurrent SPI transmission)

void GPIOTE_initirq()
{
	
NVIC_DisableIRQ(GPIOTE_IRQn);
	NVIC_ClearPendingIRQ(GPIOTE_IRQn);
	NVIC_SetPriority(GPIOTE_IRQn, APP_IRQ_PRIORITY_LOW); //Here is the problem


NRF_GPIOTE->CONFIG[0] =  (GPIOTE_CONFIG_POLARITY_LoToHi << GPIOTE_CONFIG_POLARITY_Pos)
					   | (0x10 << GPIOTE_CONFIG_PSEL_Pos)   //
					   | (GPIOTE_CONFIG_MODE_Event << GPIOTE_CONFIG_MODE_Pos);
NRF_GPIOTE->INTENSET  = GPIOTE_INTENSET_IN0_Set << GPIOTE_INTENSET_IN0_Pos;

 __NOP();
 __NOP();
 __NOP();

 NRF_GPIOTE->EVENTS_IN[0] = 0;
 NRF_GPIOTE->INTENSET = GPIOTE_INTENSET_IN0_Enabled << GPIOTE_INTENSET_IN0_Pos;
 NVIC_EnableIRQ(GPIOTE_IRQn);

}

void GPIOTE_IRQHandler(void)
{
		process_irq();
		NRF_GPIOTE->EVENTS_IN[0] = 0;
}

process_irq()
{
	do
	{
		isr();
	}while(nrf_gpio_pin_read(IRQ) == 1)
}

On Raspberry Pi the following code was executed to handle interruptions:

    //port_EnableIRQ(); 
    //enable ScenSor IRQ before starting
	// set Pin 24 generate an interrupt on high-to-low transitions
	// and attach process_deca_irq() to the interrupt

if ( wiringPiISR (IRQ_PIN, INT_EDGE_RISING, &process_deca_irq) < 0 ) {
  printf("Unable to setup ISR\r\n");
}

[Hung Bui]

I don't think it's a good idea to handle everything in a IRQ handler and stay there until the pin is released. Don't think you gonna receive the SPI interrupt if you already in a highest level priority context.

My suggestion for you is to set a flag when in IRQHandler, and execute the SPI transmission when you are back to the main loop.

When you mentioned you are using APP_IRQ_PRIORITY_LOW and APP_IRQ_PRIORITY_HIGH, do you have the softdevice also running ?