GPIOTE Interrupt nRF51822 freezing

[Guillaume Levant]

Hi,

I am writing a firmware for one of my custom boards which use GPIOTE to detect interrupt for 3 GPIOs inputs (P0.03, P0.06 and P0.09, both with internal pull-ups) and one pin set as an output (P0.05). Everything is working perfectly until the P0.09 pin goes low, then the device is freezing and does not respond to any interrupt.

I tried to debug this problem using RTT by asking to write a line when the P0.09 interrupt happens, but I never saw this line.

First, I initialize the gpiote module and the gpiote output on P0.05, and set it to 1 :

// Initialize the GPIOTE Peripheral
nrf_drv_gpiote_init();

// Configure P0.05 pin as output
nrf_drv_gpiote_out_config_t p5_config = GPIOTE_CONFIG_OUT_TASK_HIGH;

// Initialize P0.05 pin as output
nrf_drv_gpiote_out_init(5, &p5_config);

nrf_drv_gpiote_out_set(5);

Here as the configuration for the gpiote pins :

// Configuration for P0.06 Interrupt Pin
    nrf_drv_gpiote_in_config_t p6_config =
    {
        .sense = NRF_GPIOTE_POLARITY_LOTOHI,
        .pull = NRF_GPIO_PIN_PULLUP ,
        .is_watcher = false,
        .hi_accuracy = false
    };

    // Configuration for P0.03 Interrupt Pin
    nrf_drv_gpiote_in_config_t p3_config =
    {
        .sense = NRF_GPIOTE_POLARITY_HITOLO,
        .pull = NRF_GPIO_PIN_PULLUP ,
        .is_watcher = false,
        .hi_accuracy = false
    };

    // Configuration for the P0.09 Interrupt Pin
    nrf_drv_gpiote_in_config_t p9_config =
    {
        .sense = NRF_GPIOTE_POLARITY_HITOLO,
        .pull = NRF_GPIO_PIN_PULLUP ,
        .is_watcher = false,
        .hi_accuracy = false
    };

Then I init and enable each GPIOTE interrupt :

// Initialize P0.06 Interrupt Pin
    nrf_drv_gpiote_in_init(6, &p6_config, gpiote_evt_handler);

    // Enable Interrupts from P0.06 interrupt pin
    nrf_drv_gpiote_in_event_enable(6,true);

    // Initialize P0.03 Interrupt Pin
    nrf_drv_gpiote_in_init(3, &p3_config, gpiote_evt_handler);

    // Enable Interrupts from P0.03 interrupt pin
    nrf_drv_gpiote_in_event_enable(3,true);

    // Initialize P0.09 Interrupt Pin
    ret_code_t ret_code;
    ret_code = nrf_drv_gpiote_in_init(9, &p9_config, gpiote_evt_handler);
#if defined(NRF_LOG_USES_RTT) && (NRF_LOG_USES_RTT == 1)
    if(ret_code == NRF_SUCCESS)
			SEGGER_RTT_WriteString(0, "P0.09 GPIOTE init state : NRF_SUCCESS.\n");
    else if(ret_code == NRF_ERROR_INVALID_STATE)
			SEGGER_RTT_WriteString(0, "P0.09 GPIOTE init state : NRF_ERROR_INVALID_STATE.\n");
    else if(ret_code == NRF_ERROR_NO_MEM)
			SEGGER_RTT_WriteString(0, "P0.09 GPIOTE init state : NRF_ERROR_NO_MEM.\n");
    else
			SEGGER_RTT_printf(0, "P0.09 GPIOTE init state : %ld.\n", (uint32_t)ret_code);
#endif

    // Enable Interrupts from P0.09 interrupt pin
    nrf_drv_gpiote_in_event_enable(9,true);

With this configuration, all the GPIOs are doing perfectly their jobs excepted when the P0.09 interrupt occurs, which freezes everything. The intialization of the gpiote input for P0.09 returns NRF_SUCCESS, and the following channels are used for each GPIOTE event (returned by channel_port_alloc function during the initializiation of the gpiote pin events) :

• P0.05 : channel 0

• P0.06 : channel 4

• P0.03 : channel 5

• P0.09 : channel 6

That all the informations that seemed useful to me about this problem. I am working on a nRF51822 QFACA1, with SDK v11.0.0 and softdevice s130 nrf51 v2.0.0.

Do you have an idea of how to solve this problem ?

Best regards,

Guillaume

[Guillaume Levant]

I set it the priority of gpiote level to APP_IRQ_PRIORITY_HIGH, and the BLE is still working (I see BLE_GAP_EVT_CONNECTED and BLE_GAP_EVT_DISCONNECTED, and also read and write requests). But I noticed something interesting : The interrupt on P0.09 is active when the pin is low, and then the problem described above happens. But on a BLE disconnection event, I send an I2C command to a IC that sets the P0.09 high, and then the other interrupts are working even if the disconnection comes after the interrupt, and they works until P0.09 goes low again. So it seems to be link to the fact that P0.09 is low, but I can't understand why. In you opinion what piece of my code is missing to permit you to help me further ?