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Web browser controlled 16x16 Bi-Color LED-Matrix

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This is my somewhat crazy networked controlled bi-color LED matrix build:

 

 

post-19-14264605244473_thumb.jpg
 
It’s build around the TI TLC59281 as current sink column controller and a shift-register and PNP transistors as row controllers (and current source). I am using two TLC59281s one for red and one for green. Each sink controls two 8x8 LED matrix displays such that the rows of the two matrices are common. An NXP LPC1114 controls these two displays and is itself controlled via a simple SPI-protocol. The LPC1114 is running at 50MHz and updates the two led-matrices completely around 50 times a second and has 6-bit color depth per color (i.e 12-bit colors). It receives commands from the SPI bus at 1MHz, and allows the SPI bus to be shared amongst multiple display controllers. Each controller is assigned an area of the total “screen space” and simply ignores draw operations outside of this space.

In the video above I have two LPC1114s and one Stellaris Launchpad:
 

post-19-14264605244131_thumb.png


The Stellaris Launchpad runs lwIP and has a simple web server that accepts simple draw commands (put single pixel, put multiple pixels, clear). I’ve written a simple JavaScript HTML page that allows the LED matrix to be controlled from a web browser. Currently, the web-page is not served by the Stellaris Launchpad, but I'm working on that one (should be quite straight forward). I am supplying my LED Matrix PCB with 5V directly from an USB power adapter. Unfortunately, the PNPs on the PCB feed the matrix the same voltage as the TLC59281s and the 74HC595, so the ICs are running off 5V as well, which wasn't the plan at all :-)

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Oh, and BTW, source code will be available shortly. I just need to do some cleanups :-)

 

"shortly" turned out to be 7 months, and I haven't made any of the planned "cleanups". However, the code is now available at github. Stellaris code is at https://github.com/xpgdk/networked-led-matrix-controller, while the LPC code is at https://github.com/xpgdk/lpc-led-matrix-controller

 

Questions and comments regarding the code are welcome. I still have plans to do quite a bit of cleanup, but I just don't have the time for it currently.

Thanks to @@hongphuc6789 for reminding me of releasing the code.

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