Sinclair C5duino LCD Touchscreen

This project is no longer supported. The content below is provided for information only.
The C5duino LCD Touchscreen

This has now moved into the X-Pod section.

Now that we have a modern version of the Sinclair C5 Control Box (C5duino) that we can communicate with over a serial connection I will build the first display for it, a touchscreen LCD which is the same screen used in my previous C5 Touch project.

Component List

Construction is much simpler than the C5duino box, the only modification needed is to create a connection between the VIN, GND, TX1, RX1 on the Arduino MEGA to allow a connection to be made to the C5duino box at the back of the Sinclair C5.

To help sourcing the components needed to build the C5duino LCD Touchscreen I have provided links to the relevant items on Ebay. As usual, it is up to you where you get your components from, the links I provide are purely to show you the item I am talking about.

The Arduino Mega

The pins highlighted below need to be attached to the 4 way connector. I did this by running 4 wires from each pin to a small PCB stripboard which had the connector soldered on.

Arduino Mega Pin Connections

The wiring of the connector must match the connector on the C5duino circuit board, except TX1 & RX1 must be reversed. So TX1 on the Arduino Mega must be connected to RX on the C5duino board and RX1 (On Arduino Mega) must be connected to TX on the C5duino.

Software Download

Here is the software for this project. You will need to download and install the Arduino program from and then upload this to your Arduino Mega board. Instructions for uploading programs with an Arduino are provided on the offical website.

C5duino V2.0 Firmware
C5 LCD Touchscreen V2.0 Firmware
Arduino Libraries (LCD etc)

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