Can't get app_button handler to fire

[Primož Kralj]

Hello,

I'm trying a very simple thing; to light a LED on button press. I'm using SDK 9.0.0, nRF51 and SoftDevice 110. However, button handler is not firing.

So, APP_BUTTON_INIT macro is now non-existent (documentation still refers to it though) and app_button_init() takes only 3 args, last one, whether scheduler should be used, is now omitted. This was discussed here too but did not help me in anyway. Also, I do not want to use a scheduler.

So what am I doing wrong that the handler is not firing?

Here is my code (main()):

int main(void) {
    nrf_gpio_cfg_output(11); // LED
    static app_button_cfg_t p_button[] = {{8, APP_BUTTON_ACTIVE_LOW, NRF_GPIO_PIN_PULLUP, button_handler}}; // Button
    APP_TIMER_INIT(APP_TIMER_PRESCALER, APP_TIMER_MAX_TIMERS, APP_TIMER_OP_QUEUE_SIZE, false);
    APP_GPIOTE_INIT(1);
    app_button_init(p_button, sizeof(p_button) / sizeof(p_button[0]), BUTTON_DEBOUNCE_DELAY); // 50ms debounce
    app_button_enable();

    while(true) { /* do nothing */ }
}

And handler (very simplified):

static void button_handler(uint8_t pin_no, uint8_t button_action)
{
     nrf_gpio_pin_toggle(11);
}

[Einar Thorsrud]

It does not look like you have started the LFCLK. This is done implicitly if you enable the SoftDevice (using sd_ble_enable()). When that is not done, as seems like the case here, you have to request the LFCLK. You can do this in several ways. On way is to add the clock driver (nrf_drv_clock.c) to your project (and include the corresponding header file. Then you can request the clock in the following way:

uint32_t err_code = nrf_drv_clock_init(NULL);
APP_ERROR_CHECK(err_code);
nrf_drv_clock_lfclk_request();

[Primož Kralj]

Thanks, this is exactly what I was missing!