Controlling RGB LED display on Raspberry Pi GPIO via PixelPusher protocol

Code is (c) Henner Zeller [email protected], license: GNU General Public License, Version 3.0

For details of the RGB Matrix library used and how to connect, see the github over at Raspberry Pi RGB Matrix.

Compiling

Clone with --recursive to get the RGB matrix submodule when cloning this repository:

git clone --recursive https://github.com/hzeller/rpi-matrix-pixelpusher.git

Running

Simply run the program as root (which is needed to access the GPIO pins).

 $ make
 $ sudo ./pixel-push

These are the available options

 usage: ./pixel-push <options>
 Options:
     -r <rows>     : Display rows. 16 for 16x32, 32 for 32x32. Default: 32
     -c <chained>  : Daisy-chained boards. Default: 1.
     -L            : 'Large' display, composed out of 4 times 32x32
     -p <pwm-bits> : Bits used for PWM. Something between 1..7
     -g            : Do gamma correction (experimental)
     -d            : run as daemon. Use this when starting in
                     /etc/init.d, but also when running without
                     terminal (e.g. cron).

This will advertise itself as a PixelPusher http://heroicrobotics.boards.net/board/5/pixelpusher device on the network. Number of 'strips' will be number of rows, so 16 or 32 (or, in the case of the 'Large' (Option -L) display, 64) The strip-length is 32 * chained (64 for the -L display).

You can control these for instance with the Processing framework http://processing.org/. The processing framework already has a contrib library section that allows you to select PixelPusher supporting libs.

Large Display

For the 'Large' display (option -L), we are using four boards are daisy-chained 'around the corner', see beginning of the video. This is an example how to compose more complex and larger displays out of smaller ones. See source for details and if you want to modify things.