Adafruit: 16x24 Red LED Matrix Panel
Adafruit's 16x24 Red LED Matrix Panel uses the HT1632C LED driver. The driver has the ability to dim and flash and they can be chained together to produce large displays. The code developed for this Mini Project is based on Adafruit's original HT1632 github repository originally written for Arduino. It also uses a modified version of BoneHeader.h to support C++ originally from Andrew Miller's github repository.
Inputs and Outputs
A single matrix panel can be powered directly off of the BeagleBone's 3.3V supply (running only on USB power). The interface is a bit-banged serial interface requiring 3 pins: chip select (active low), write clock (rising edge trigger), and data. The HT1632C also has a read pin, but it is not populated or used in the example code developed for this Mini Project.
The pin mappings
P9 pin # (BeagleBone pin) -> Panel pin (wire color)
1 (GND) -> GND (black)
3 (VDD_3V3EXP) -> VCC (red)
15 (R13/GPIO1_16) -> CS0 (white)
23 (V14/GPIO1_17) -> DATA (yellow)
25 (A14/GPIO3_21) -> WR (orange)
Sample C++ Code
The code shown below is sample code to demonstrate the 16x24 Red LED Matrix Panel.
This code example and the required resources can be found in this repository