Where I can find the tutorial nrf5-ble-tutorial-characteristic in SDK12.3 version?

[B]

The tutorial nrf5-ble-tutorial-characteristic is about SDK11, but I need in SDK12.3. Where I can find it?!

Best wishes

[MartinBL]

Unfortunately you can't. The tutorial was written for SDK 11, and I haven't had the time to port it to all successive SDKs. In this thread you will find a port for SDK 13 though. But if you are using nRF51 that might not be of any use to you.