Can nrf52840 usbd work with softdevice?

[nrfmote]

The nrf52840 usbd examples of peripheral in SDK 13.0.0 worked fine. I want usb work with BLE softdevice and there are lots of conflicts between nrf drv and softdevice. Is there any example of usbd working together with ble softdevice?

[Roger Clark]

Interesting.

I'd only tried the USBD demo, and it worked, (though some driver issues), and I presumed that it was compatible with the SD, but perhaps because its an Alpha SDK version its not working yet

[Sigurd]

Hi,

There shouldn't be any conflict between using the USBD peripheral and the SoftDevice. There is no BLE together with USBD example yet. What BLE example are you using? What warnings/errors are you getting when compiling?

[nrfmote]

I want to transmit the date between ble and usb and I use the example ble uart and USB CDC ACM. There is no errors when compiling. The functions nrf_drv_power_init() and nrf_drv_power_usbevt_init() in usb_start() will crash after ble_stack_init(). The function ble_stack_init() may be executed the after usbd init. But when the ble_stack is enabled, the power_usb_event_handler() can not reached.

[Sigurd]

Hi,

I just tested this without any problems. Only thing I had to do was to comment out the buttons_leds_init() function used in the ble_app_uart code, so it didn’t overwrite the button functionality used for the USBD part of the code. My main code looks like this:

int main(void)
{
    uint32_t err_code = 0;
    bool erase_bonds;
    
    uint32_t ret = 0;    

    // Initialize.
    APP_TIMER_INIT(APP_TIMER_PRESCALER, APP_TIMER_OP_QUEUE_SIZE, false);
    uart_init();
    err_code = NRF_LOG_INIT(NULL);
    APP_ERROR_CHECK(err_code);
    
    NRF_LOG_INFO("\r\nUART Start!\r\n");
    
    ret = nrf_drv_power_init(NULL);
    APP_ERROR_CHECK(ret);
    
    ret = nrf_drv_clock_init();

    APP_ERROR_CHECK(ret);
    
    
    NRF_LOG_INFO("Hello USB!\r\n");

    /* Configure LEDs */
    bsp_board_leds_init();
    bsp_board_buttons_init();


    serial_number_string_create();
    
    ret = app_usbd_init();
    APP_ERROR_CHECK(ret);

    app_usbd_class_inst_t const * class_cdc_acm = app_usbd_cdc_acm_class_inst_get(&m_app_cdc_acm);
    ret = app_usbd_class_append(class_cdc_acm);
    APP_ERROR_CHECK(ret);

    bool last_usb_conn_status = false;
    usb_start();

    
    NRF_LOG_INFO("Enabling BLE part!\r\n");
    //buttons_leds_init(&erase_bonds);
    ble_stack_init();
    gap_params_init();
    services_init();
    advertising_init();
    conn_params_init();
   
    err_code = ble_advertising_start(BLE_ADV_MODE_FAST);
    APP_ERROR_CHECK(err_code);
    
    // Enter main loop.
    for (;;)
    {
        
        last_usb_conn_status = usb_connection_handle(last_usb_conn_status);

        if (bsp_board_button_state_get(BTN_CDC_DATA_SEND))
        {
            static int  frame_counter;

            sprintf(m_tx_buffer, "Hello USB CDC FA demo: %u\r\n", frame_counter);

            ret = app_usbd_cdc_acm_write(&m_app_cdc_acm, m_tx_buffer, sizeof(m_tx_buffer));
            if (ret == NRF_SUCCESS)
            {
                ++frame_counter;
            }
        }

        if (bsp_board_button_state_get(BTN_CDC_NOTIFY_SEND))
        {
            ret = app_usbd_cdc_acm_serial_state_notify(&m_app_cdc_acm,
                                                       APP_USBD_CDC_ACM_SERIAL_STATE_BREAK,
                                                       false);
            UNUSED_VARIABLE(ret);
        }

        UNUSED_RETURN_VALUE(NRF_LOG_PROCESS());
        
        
        power_manage();
    }
}

[nrfmote]

Thanks for your example code.If I plug in the usb header after start the power the nrf52840, computer will not find the USB CDC device and the LED1's state do not change. Only when I plug in the use header first and then power on the nrf52840, or reset the chip, the computer will find the USB CDC device. In debug mode, it can be found that the function power_usb_event_handler() only work once when program start. After ble_stack_init(), it can not reach at power_usb_event_handler(). It is same with my code.