Bluetooth Low Energy garage door opener remote control

This is yet another Bluetooth Low Energy (BLE) remote control application that
can be used to control a garage door drive from a smartphone.

A particularity of this project is that BLE advertising PDUs are used,
thereby avoiding connection setup delays. The system thus responds as
quickly to a remote control command as a classical hardware garage door
transmitter receiver combination would do. There is one-way communication
from the smartphone to the receiver only, which is secured by HMAC. The idea
was to keep everything simple, both the hardware as well as the software.

Building the receiver software

1. Make sure that the following is installed

   • Arm GCC toolchain
   • Nordic Semiconductor nRF5 SDK v17.0.0
   • GNU make and Python3

2. cd nrf52/acn52832_s132

3. Adapt SDK_ROOT, GNU_INSTALL_ROOT and GNU_VERSION in the Makefile

4. make

5. Flash the soft device (s132_nrf52_7.0.1_softdevice.hex), which is part of the SDK

6. Flash the compiled software image (_build/nrf52832_xxaa.hex)

Building the Android App

1. Make sure that Android Studio and an Android SDK is installed

2. Use Android Studio/Gradle to build the App