This project was created to promote our new vinyl record department in our Hereford store, the idea being to place this scrolling text message display in the shop window to entice customers to browse. As you can see from the short video below, I’ve yet to build the final display project – what you see is a breadboard prototype.
Any message can be displayed within reason – it is simply edited from within the firmware. One of the challenges of this project was the fact that although there are many scrolling text projects to be found on the web and shown on You Tube, they invariably use pre-built software display libraries to cope with the driving of the 8×8 matrix displays, the communication between the microcontroller and MAX7219 display driver, and then the animation of the text – these libraries give you no real insight into what is actually going on inside the microcontroller.
I wanted to ‘roll my own’ display/ comms/ animation code in C language, but found very sparse information available. I hope to set this right over the course of this blog post, and hopefully you will want to create your own scrolling text display, or just use the information on offer here as a tutorial to go on to better and bigger things.
Here is a pdf file containing the C language source code for the project. It was compiled using Microchip’s free XC8 C complier, and flashed to the microcontroller with the PICkit 3.