how to discovery 128bit characteristic UUID which is totally different form 128bit service UUID

[QYQ]

Hi, I am trying to make nrf52832 as a UART certal. The service UUID and characteristic UUID of peripheral are shown as the following picture. They are all 128bit and quite different. In the example of "ble_app_uart_c", the BLE_UUID_NUS_SERVICE, BLE_UUID_NUS_TX_CHARACTERISTIC, and BLE_UUID_NUS_RX_CHARACTERISTIC are all 16bit. throught this example, I can get service UUID but can not get characteristic UUID. the version of SDK is 12.1.  How can i get the characteristic UUID? Could anyone help me or give me some suggestion?  thanks.

[Turbo J]

Unless I am mistaken, you need to add at least two vendor specific UUIDs using sd_ble_uuid_vs_add() API call.

The primary service seems to use the base UUID from bluetooth standard, but the characteristics don't and they also seem to change the "wrong" byte(s) - that is why you need two uuids. Nordic softdevice only allows to "re-use" the same base UUID if byte 12 and 13 changes.