RE: Unable to read packets from custom BLE Characteristic

bojan — Tue, 13 Oct 2020 12:28:08 GMT

I think I resolved the issue. It might be useful for someone in the future so here is what I do when BLE_GATTS_EVT_WRITE event happens:

case BLE_GATTS_EVT_WRITE:

    if(p_ble_evt->evt.gatts_evt.params.write.handle == p_mercury_service->timestamp_handshake_char_handles.value_handle){
        NRF_LOG_WARNING("Data received over desired custom BLE Characteristic!");
        NRF_LOG_WARNING("BLE Data length: %d", p_ble_evt->evt.gatts_evt.params.write.len);    
        NRF_LOG_HEXDUMP_INFO(p_ble_evt->evt.gatts_evt.params.write.data, p_ble_evt->evt.gatts_evt.params.write.len)
    } else {
        NRF_LOG_WARNING("Data received over some other cusotm BLE Charecteristic!");
    }

    break;

with

if(p_ble_evt->evt.gatts_evt.params.write.handle == p_mercury_service->timestamp_handshake_char_handles.value_handle)

condition, I basically check if received data coming from desired custom BLE Characteristic. If affirmative, we can access the data through p_ble_evt->evt.gatts_evt.params.write.data pointer. The length of received data can be read from p_ble_evt->evt.gatts_evt.params.write.len !

Cheers,

Bojan.