It’s easy to make a scrolling text ticker with an Arduino Uno and multiple MAX7219 8×8 LED matrix modules. Just 5 connections between the Arduino and the first module are required: 3 for data and 2 for power. Multiple modules can be daisychained. Depending on the power available you can connect many of these modules together.
How-to: interactive ticker display
In this short tutorial you can read how to easily make an interactive ticker display. The display will show a preprogrammed line of text first. After that you can type in some characters and send them to the dispay over the serial connection.
Wiring Arduino and MAX7219 8×8 LED matrix modules
Only the first display needs to be wired to the Arduino. Any additional modules will be daisychained. See this example featuring 3 displays:
To make it easy to communicatre with the matrix-modules we will be using the “MaxMatrix”-library which you can download here: https://github.com/riyas-org/. There you can also find a code example which we will adapt and make interactive. It will allow you to send text from yout computer to the display over the serial connection.
Example code: interactive scrolling text display
After installing the MaxMatrix library you can download or copy/paste the sketch you see below. A few values you can customize:
The value “maxInUse” will set the number of modules conected to the Arduino;
The value “scrollSpeed” will set the scrolling speed: lower value means faster scrolling;
And “m.setIntensity()” sets the LED intensity from 0 tot 15: higher value means brighter LEDs.
After you have uploaded the sketch to the Arduino, you will first see the predefined text scrolling along. After that, you can open the serial monitor in the Arduino-IDE and send a new text (max. 64 characters) to the display.
This sketch is also available on GitHub: https://github.com/oneguyoneblog/