Modifying UART peripheral example to send data without using UART peripheral

[BattleDroid]

SDK: 15.1
IDE: Keil
Softdevice: S132 v6.0

Hello, I am using the ble_app_uart example as a starting point.  My goal is to send 5 bytes every 5 seconds to another nRF52 Development kit acting as the Central.  For the central, I used ble_app_uart_c example.  I have established successful link between the peripheral and client to send 5 bytes of my data.  To do this, I created an App Timer, that every 5 seconds calls ble_nus_data_send() in the handler and transmits the array of 5 bytes to the central.  This is working properly and I am able to see the 5 bytes of data every 5 seconds at the central side using a terminal program.

The question is, on the peripheral side, I would like to disable the UART peripheral since I no longer need it since I am plugging in my own data into ble_nus_data_send().  When I try to disable the UART by commenting out uart_init() inside the main() function, the devices stop connecting
 

uart_init();

 

What code needs to be modified in order to disable the UART without breaking the functionality I described above?

[hmolesworth]

Try not sending received data from BLE to the uart; modify this code assuming you haven't already done that:

static void nus_data_handler(ble_nus_evt_t * p_evt)
{

    if (p_evt->type == BLE_NUS_EVT_RX_DATA)
    {
        uint32_t err_code;

        NRF_LOG_DEBUG("Received data from BLE NUS. Writing data on UART.");
        NRF_LOG_HEXDUMP_DEBUG(p_evt->params.rx_data.p_data, p_evt->params.rx_data.length);

        for (uint32_t i = 0; i < p_evt->params.rx_data.length; i++)
        {
            do
            {
                err_code = app_uart_put(p_evt->params.rx_data.p_data[i]);
                if ((err_code != NRF_SUCCESS) && (err_code != NRF_ERROR_BUSY))
                {
                    NRF_LOG_ERROR("Failed receiving NUS message. Error 0x%x. ", err_code);
                    APP_ERROR_CHECK(err_code);
                }
            } while (err_code == NRF_ERROR_BUSY);
        }
        if (p_evt->params.rx_data.p_data[p_evt->params.rx_data.length - 1] == '\r')
        {
            while (app_uart_put('\n') == NRF_ERROR_BUSY);
        }
    }

}

[BattleDroid]

Hello hmolesworth,

I have already commented out the contents of this handler, see below:

static void nus_data_handler(ble_nus_evt_t * p_evt)
{
//
//    if (p_evt->type == BLE_NUS_EVT_RX_DATA)
//    {
//        uint32_t err_code;

//        NRF_LOG_DEBUG("Received data from BLE NUS. Writing data on UART.");
//        NRF_LOG_HEXDUMP_DEBUG(p_evt->params.rx_data.p_data, p_evt->params.rx_data.length);

//        for (uint32_t i = 0; i < p_evt->params.rx_data.length; i++)
//        {
//            do
//            {
//                err_code = app_uart_put(p_evt->params.rx_data.p_data[i]);
//                if ((err_code != NRF_SUCCESS) && (err_code != NRF_ERROR_BUSY))
//                {
//                    NRF_LOG_ERROR("Failed receiving NUS message. Error 0x%x. ", err_code);
//                    APP_ERROR_CHECK(err_code);
//                }
//            } while (err_code == NRF_ERROR_BUSY);
//        }
//        if (p_evt->params.rx_data.p_data[p_evt->params.rx_data.length - 1] == '\r')
//        {
//            while (app_uart_put('\n') == NRF_ERROR_BUSY);
//        }
//    }
//
}

Even with this, I cannot remove the uart_init() function call without loosing functionality

[hmolesworth]

Did you change the data handler? How does the nus handle incoming data over BLE? I run the uart service and only modify the data_handler and disable uart_init() and all works as expected; I don't have anything else different.

static void services_init(void)
{
    uint32_t           err_code;
    ble_nus_init_t     nus_init;
    nrf_ble_qwr_init_t qwr_init = {0};

    // Initialize Queued Write Module.
    qwr_init.error_handler = nrf_qwr_error_handler;

    err_code = nrf_ble_qwr_init(&m_qwr, &qwr_init);
    APP_ERROR_CHECK(err_code);

    // Initialize NUS.
    memset(&nus_init, 0, sizeof(nus_init));

    nus_init.data_handler = nus_data_handler; // <==

    err_code = ble_nus_init(&m_nus, &nus_init);
    APP_ERROR_CHECK(err_code);
}

[BattleDroid]

You are correct, thank you for your prompt reply.  I am now able to send data without calling uart_init();