GPIO Interrupt not triggered

[Hieu]

I am trying to set up a button interrupt by adding the following functions:

void button_interrupt_handler(nrf_drv_gpiote_pin_t pin, nrf_gpiote_polarity_t action)
{
    nrf_gpio_pin_toggle(LED_4);
}

void button4_config()
{
    nrf_drv_gpiote_in_config_t config;
    memset(&config, 0, sizeof(nrf_drv_gpiote_in_config_t));
    config.sense = NRF_GPIOTE_POLARITY_HITOLO;
    config.pull = NRF_GPIO_PIN_NOPULL;
    config.hi_accuracy = false;
    config.is_watcher = false;
    
    nrf_drv_gpiote_in_init(BUTTON_4, &config, button_interrupt_handler);
    nrf_drv_gpiote_in_event_enable(BUTTON_4, true);
    
}
int main(void)
{
    // ...
    button4_config();
    // ...
}

When I tried to press the button, my interrupt is never called. Not even once.

Thinking that maybe the problem is because I was using BUTTON_4, I have also tried to replace it with pin 29 and use an external button. That doesn't work either.

What could I be missing?

[Petter Myhre]

I can't see that you are calling nrf_drv_gpiote_init() anywhere

Edit 1: Try this:

void button_interrupt_handler(nrf_drv_gpiote_pin_t pin, nrf_gpiote_polarity_t action)
{
    nrf_gpio_pin_toggle(LED_4);
}

static void button4_config()
{
    nrf_drv_gpiote_in_config_t config;
    memset(&config, 0, sizeof(nrf_drv_gpiote_in_config_t));
    config.sense = NRF_GPIOTE_POLARITY_HITOLO;
    config.pull = NRF_GPIO_PIN_PULLUP;
    config.hi_accuracy = false;
    config.is_watcher = false;

    nrf_drv_gpiote_in_init(BUTTON_4, &config, button_interrupt_handler);
    nrf_drv_gpiote_in_event_enable(BUTTON_4, true);

}

/**
 * @brief Function for application main entry.
 */
int main(void)
{
    ret_code_t err_code;

    nrf_gpio_cfg_output(LED_4);
        
    err_code = nrf_drv_gpiote_init();
    APP_ERROR_CHECK(err_code);

    button4_config();

    while (true)
    {
    }
}

[Hieu]

Hi Petter, I indeed missed that function call. However it is coincidentally covered when I called app_pwm_init() at an earlier point in my application, so it does not seem to be the problem.

I have however added the call into my button4_config() as instructed in the GPIOTE driver page, however the button interrupt is still not called.

[Hieu]

Hi Petter,

Sorry for being late with the follow up. I just got out of a very tight deadline rush.

I have tried explicitly calling the function nrf_drv_gpiote_init() as you shown in your code. However that does not help. It returns NRF_ERROR_INVALID_STATE indicating that GPIOTE has already been initialized by something else.

[Hieu]

Also, my application is based off of the ble_app_uart example so during setup it also call:

uint32_t err_code = bsp_init(BSP_INIT_LED /* | BSP_INIT_BUTTONS */,
                                 APP_TIMER_TICKS(100, APP_TIMER_PRESCALER), 
                                 bsp_event_handler);

Perhaps this matters? I tried remove | BSP_INIT_BUTTON from the parameter and managed to make the button works somehow. However, it seems the button is extremely sensitive, just my hand touching it causes LED 4 to blink rapidly.

[Hieu]

*update: fixed that extreme sensitivity issue. Turns out I should have the GPIO pin being pulled up, so I did just that.

So my new question would be, is it impossible to overwrite the button behavior set by bsp_init()?