Setting up a board for RelayKeys

If you have a pre-prepared Bluetooth stick (for example, from Ace Centre), you don't need to read this section. If you are buying your electronics to use, then read on.

A wide range of Arduino boards supports HID (Human Interface Device). Often these are to emulate simple keypress' but to do more complex things like send one or modifier keys with a key - or to emulate holding a key down for a set period of time is either impossible or difficult to implement. Adafruit has developed the firmware on their Bluefruit nrf* range of boards to emulate HID keyboards well using their AT Commands.

Currently, RelayKeys is designed to work with

• the Adafruit Raytac nrf52840 dongle (Buy from the piHut or Digikey). Note this is the cleanest looking solution and one of the cheapest. We have pre-prepared firmware for this for both receiving and sending.

• Adafruit Feather nRF52840 Express (Buy in the UK from Pimoroni). Note you can use this or the itsybitsy with a battery and have relaykeys work without connecting it directly to your AAC device.

• or with the Adafruit itsybitsy nrf52840

• or with lesser support for the The Adafruit - Bluefruit LE Friend - nRF51822 - v3.0 (Buy in the UK from Pimoroni). Although Note: We really aren't supporting the LE Friend much - we do hear it works, but dragons, beware! See below for details on configuring these.

If you are using a receiver dongle - follow the same guidance below but you will also need to copy over the firmware file for the dongle. Same procedure - different file name

Once you have your hardware you need to configure and set them up to work with relaykeys. Read on for how you do this for each device.