Dingding
Bluetooth LE based doorbell using ARM Mbed and the Nordic Semiconductor NRF51 devkit.
The python files run on a Raspberry-Pi with a speaker and a bluetooth module. The code in mbed/ runs on the NRF51-DK.
Model for the 3D-printed case: https://cad.onshape.com/documents/57066aa5e4b06e09978153a8/w/bd81a80ae9c757985bd70ad1
