Adafruit: Bicolor LED Square Pixel Matrix
Overview: 2 Wiring: 0 Code: 1 git/Compiles with make: 0 Demo: 0 Total: 3 Comments: It's good you have it working. Now you need to fix up this page. Assume you are writing to someone who wants to know how to use the device. Show a picture of it. Note the importance of soldering the display on correctly. Give wiring instructions. Be specific, where do I wire the power? Where does the clock go, etc. How is the voltage level converter wired in? Show a picture of the wiring. Clean up Greg's code an put it in your github repository. Include a Makefile Give me a demo. Can you have this done in a week? 24-Oct-2012?
Embedded Linux Class by Mark A. Yoder
Page by Alex Drane, Peter Ngo
This page details project work done while working on the 8x8 Bicolor LED Pixel Matrix from Adafruit found here: Store Link
IMPORTANT!!! When soldering the led matrix to the controller make sure that it is placed correctly. If it is not, then the device will still communicate but the LED Matrix will not turn on.
The device relies on the 5V source on the board and to insure functionality an I2C voltage level converter is used to boost the 3.3V I2C voltage to 5V. The voltage level converter is hooked up according to the photo. Starting from the top left of the device: SCL 5V, 5V Rail, Reset(Pulled up to 3.3V), SCL 3.3V In. Bottom Left: SDA 5V, Ground, 3.3V, SDA 3.3V.
The LED Matrix is wired from left to right: 5V, Ground, SDA, SCL.
The tenth pin from the Right on row 1 of the P9 IO Rail on the Beagle (Count from the 5V Line in) is the SCL pin and the pin on row 2 is the SDA pin. Starting from the right on P9 top row is: Ground, 3.3V, Skip, 5V.
The current LED Matrix is fully functional except for a minor issue with alignment of the rows. It is shifted up by one LED and puts the top row at the bottom. The former issues encountered with the device was due to a miss-wiring of the matrix to the I2C Part.