LIBUARTE on ble_app_uart with DMA

[Bar1]

Hi All,

I have 2 boards nrf52840 pc10056 and I need to run ble_app_uart using LIBUARTE with DMA in order to obtain a more robust uart communication

I would like to use an uart DMA that will work in background saving the byte received in a buffer (fixed length) and once that it is full having an interrupt where I can check this buffer and send it to the central unit.

Is there any easy way to set  everything up and change the code of ble_app_uart? Any suggestion??

Thanks

[Simonr]

Hi

Thank you for the clarification! Is by any chance the TX buffer not cleared after sending a message, and that is what is causing this error? If not, are you able to get an error code so we can see where exactly this error originates?

Best regards,

Simon

[Bar1]

Hi,

I do not use any TX buffer (not that I know). Because in this case I'm not writing on the UART, I'm just reading, sending to the central and make free the RX buffer. 

I cannot get an error code. In the code that I put back here, there is APP_ERROR_CHECK(err_code), but the program does not go there.

void uart_event_handler(void * context, nrf_libuarte_async_evt_t * p_evt)
{
    nrf_libuarte_async_t * p_libuarte = (nrf_libuarte_async_t *)context;
    uint32_t       err_code;
    ret_code_t ret;

    switch (p_evt->type)
    {
        case NRF_LIBUARTE_ASYNC_EVT_ERROR:
            bsp_board_led_invert(1);
            break;
        case NRF_LIBUARTE_ASYNC_EVT_RX_DATA:
            bsp_board_led_invert(2);
            err_code= ble_nus_data_send(&m_nus, p_evt->data.rxtx.p_data, &p_evt->data.rxtx.length, m_conn_handle);
            do
            {
                if ((err_code != NRF_ERROR_INVALID_STATE) &&
                    (err_code != NRF_ERROR_RESOURCES) &&
                    (err_code != NRF_ERROR_NOT_FOUND))
                {
                    APP_ERROR_CHECK(err_code);
                }
            } while (err_code == NRF_ERROR_RESOURCES);
            nrf_libuarte_async_rx_free(p_libuarte, p_evt->data.rxtx.p_data , p_evt->data.rxtx.length);    // if I remove this line of code I will have more or less the same behavior 
            break;
        case NRF_LIBUARTE_ASYNC_EVT_TX_DONE:
            bsp_board_led_invert(3);
            break;
        default:
            break;
    }
}