BLE nus multilink rx source detection

[sinany1]

I am working on a ble nus pheripheral application on nrf52810 with sdk 15.2 and s112. currently I can connect to nrf52 with 4 mobile phone at same time and send&receive string. but how can I know which phone sends the characters? 

[Edvin]

You have to check the conn_handle of the event that the string comes in. Please note that there may be a bug in the ble_nuc.c library, as the BLE_NUS_EVT_RX_DATA event doesn'f forward the conn_handle (it is designed for only one connection).

So in on_write() in ble_nus.c, look for the place it says:

evt.type                  = BLE_NUS_EVT_RX_DATA;

Then add the conn_handle to this event before it is forwarded to the p_nus->data_handler(&evt);

Add the event by adding this line before this call:

evt.conn_handle           = p_ble_evt->evt.gatts_evt.conn_handle;

Then you can check the conn_handle in the nus_data_handler:

static void nus_data_handler(ble_nus_evt_t * p_evt)
{

    if (p_evt->type == BLE_NUS_EVT_RX_DATA)
    {
        uint32_t err_code;
        uint16_t my_conn_handle = p_ble_evt->conn_handle;
        NRF_LOG_INFO("received data from conn_handle %x", my_conn_handle);
        
        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);

    ...

You need to keep track of what phone that belongs to what conn_handle. It should be the same as the conn_handle that you find in the BLE_GAP_EVT_CONNECTED event in ble_evt_handler() in main.c.

Best regards,

Edvin

[sinany1]

is it 

 uint16_t my_conn_handle = p_ble_evt->conn_handle;

or 

 uint16_t my_conn_handle = p_evt->conn_handle;

in nus_data_handler(ble_nus_evt_t * p_evt)

[Edvin]

Sorry.

p_evt->conn_handle.

It should always be the same as the event that is passed into the function.

Best regards,

Edvin

[sinany1]

Ok, thanks. seems it's gonna work. I will verify your answer after the test.