Send DFU files from one nrf52833 controller to another nrf52833 controller via BLE

RE: Send DFU files from one nrf52833 controller to another nrf52833 controller via BLE

Hung Bui — Mon, 06 Dec 2021 14:18:30 GMT

Hi Rakkumuthu,

For developing such application I strongly suggest to use a nRF Sniffer to debug. With the sniffer you can see what transmitted over the air and can greatly help to debug. You only need an extra nRF52 DK/dongle to use a sniffer.
With the sniffer you can also record a standard OTA DFU process from for example Android phone to the device to use a reference to develop your app.

Please try record the process with the nRF Sniffer and send to us for further investigation.

RE: Send DFU files from one nrf52833 controller to another nrf52833 controller via BLE

Rakkumuthu — Mon, 06 Dec 2021 13:47:12 GMT

Your understanding right. I am referring above documentation and code for my reference. But, with BLE services i got stuck with the command sent and responses reception. I am using below to enable the notification of custom board DFU service control point notification.

             uint32_t retcode = 0;
           uint8_t au8CcdVal[2] = {0};
           uint16_t payload_len = 2;
           ble_gattc_write_params_t gattc_params;
                          au8CcdVal[0] = 1;
               au8CcdVal[1] = 0;
               gattc_params.handle   = g_sCntrlPntChars.cccd_handle;
        gattc_params.len      = 2;
        gattc_params.p_value = au8CcdVal;
        gattc_params.offset   = 0;
        gattc_params.write_op = BLE_GATT_OP_WRITE_REQ;

           }
        retcode = sd_ble_gattc_write(p_ctx->conn_handle, &gattc_params);
               NRF_LOG_INFO("DFU Notif = %d",retcode);
         APP_ERROR_CHECK(retcode);

I am getting the retcode to 0. For this code, i am getting BLE_GATTC_EVT_WRITE_RSP response in BLE event handler. After that using the above code to send the select command [06 01] which is returning not error with BLE_GATTC_EVT_WRITE_RSP event. How do i extract the response from peer device to validate the offset, maxsize and crc as per the documentation. I am getting the p_ble_evt->evt.gattc_evt.params.write_rsp.len value as 0 which means no data. Please tell me the how to extract the response from peer device for dfu commands.

RE: Send DFU files from one nrf52833 controller to another nrf52833 controller via BLE

Hung Bui — Mon, 06 Dec 2021 13:34:49 GMT

Hi Rakkumuthu,

My understanding is that you want to implement DFU master code on nRF52833 to update another nRF52833 via BLE.
I would suggest to have a look at the DFU protocol documentation here and the BLE specific transport here. You can find how you can send the init packet and the actual image there.

We have an example of doing DFU Master for SPI and UART you can have a look here. It's not for BLE but I think it can be useful when you develop your own DFU master.