Turning Point Clicker Emulation with Arduino and nRF24L01
The Turning Point ResponseCard RF, often referred to as a clicker, sends user input to a hub for polling purposes. The user can select a button labeled 1-9 and 0, or A-J and the clicker will send the result to the hub which collects all of the responses. Travis Goodspeed details some of the inter-workings of the Turning Point ResponseCard RF in his blog. He found out that the device always sends it’s answer to the MAC address 0x123456. Then the payload itself is preambled with the clickers MAC address and then the user input, which is ascii 0 through 9 or a question mark. Finally the packet is terminated with a 2-byte CRC.
The heart of the clicker is a Nordic chip, nRF24E1 or nRF24LE1 for later models. This chip includes a nRF24L01 wireless transceiver, which is readily available on ebay for about $2 and can be quickly attached to an Arduino or other microcontroller. This article will discuss how to use an nRF24L01 chip along with an Arduino to emulate and extend the functionality of the Turning Point ResponseCard RF.