Configuring port events to prevent spurious interrupts

[Tania V]

Hi Nordic Semiconductor team,

I'm working with the nrf52840 MCU and I have a system off and system on routine and it's works properly (400nA current consumption in system off and 3.3µA in system on). The routine switches to system on when a button is pressed (port event) and I have read that some extra steps are needed to configure the port event.

My question is: Do I need to configure these extra steps for the port event?

Following the previous points (1 to 4), can you give me your opinion? Is this sequence correct?

//======== code ============

//To prevent spurious interrupts

    //1. Disable interrupts

    NRF_GPIOTE->INTENCLR = GPIOTE_INTENSET_PORT_Msk; 

    //2. Configure the sources (sense)

    nrf_gpio_cfg_input(NRF_DT_GPIOS_TO_PSEL(DT_ALIAS(button0), gpios), NRF_GPIO_PIN_PULLUP);

    nrf_gpio_cfg_sense_set(NRF_DT_GPIOS_TO_PSEL(DT_ALIAS(button0), gpios), NRF_GPIO_PIN_SENSE_HIGH);

    //3. Write 0 to events_port

    NRF_GPIOTE->EVENTS_PORT = 0x00000000; 

   

    //4. Enable interrupts

    NRF_GPIOTE->INTENSET = GPIOTE_INTENSET_PORT_Enabled;  //<< GPIOTE_INTENSET_PORT_Pos;

    //NVIC_EnableIRQ(GPIOTE_IRQn); //Enable the interrupt

//====================

Thank you in advance.

Regards,

Tania

[Øivind]

Hi,

Thank you for your patience. I don't think all of that is necessary. My colleague Vidar answered this on similar ticket:

You can use the sense-edge-mask in your devicetree to enable PORT detection for your pins. The GPIO driver defaults to using GPIOTE IN channel events if this mask is not set

gpio0: gpio@50000000 {

compatible = "nordic,nrf-gpio";

gpio-controller;

reg = < 0x50000000 0x200 0x50000500 0x300 >;

#gpio-cells = < 0x2 >;

status = "okay";

port = < 0x0 >;

sense-edge-mask = < 0xffffffff >;

phandle = < 0x18 >;

};

Example overlay for 'nrf52840dk_nrf52840' to use PORT event on all Port 0 pins:

nrf52840dk_nrf52840.overlay

You can find the GPIO API doc here : https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/hardware/peripherals/gpio.html.  And you have the "Button" sample demonstrating how to use the APIs here: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/samples/basic/button/README.html

[Tania V]

Thank you!