Testing

Before powering up the Display and Raspberry Pi, check the wiring over carefully and make sure everything is connected as it should be.
Power the display up first and then the Raspberry Pi.

Lets start by creating a directory in which to keep the code. So open an LX terminal session (you can use SSH with the Pi ) if you prefer and enter the following command.
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$ mkdir display16x32
$ cd display16x32

We now need to fetch the code from Henner Zeller's original project using the command:

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$ git clone https://github.com/hzeller/rpi-rgb-led-matrix/

This code is C source code, so we need to compile it before we can run it. It also requires a small change for the wiring layout we're using. Enter the following commands:

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$ cd rpi-rgb-led-matrix/lib
$ nano Makefile

(Or substitute your editor of preference.)

Enable this line in the Makefile (it’s commented out by default):

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DEFINES+=-DRGB_CLASSIC_PINOUT

Save the changes to the file, then exit the editor and type...

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$ cd ..
$ make
To run the test program, enter the command:
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$ sudo ./led-matrix
The test program can also display a scrolling message. Infortunately, this message was designed for a 32x32 display and so you will only see the top half of the message. In the next section I will show you how to create your own message image using GIMP.

Try out the oversized message anyway using:
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$ sudo ./led-matrix 1 runtext.ppm
This guide was first published on Mar 13, 2014. It was last updated on Mar 13, 2014. This page (Testing) was last updated on Nov 20, 2019.