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AVR Matrix? Who needs a VU-Meter for XMMS ?

Not me? Just did some more or less useful stuff with my [STK-500 dev boad](http://www.atmel.com/dyn/products/tools_card.asp?tool_id=2735). I took 64 leds and formed a **8×8 matrix** out of them, solderd them onto 2 layers of ciruit boards. The leds are connected to 2 8Bit IO-Busses of an **Atmel AT90S8515**. I use one bus to select a row and the other bus to write on byte into a led-row. since iam changing the rows very quick, you won’t see an flicker. actually it’s 100hz refresh rate.

Then i a wrote a litte library in C using [AVR-GCC](http://gcc.gnu.org/) to access the matrix like an framebuffer. Also funny stuff like scroll text is included in that lib. On top of this a wrote some code to interface the Atmel to PC’s serial port. That incoming data from the SIO get’s displayed on the led matrix.
So that an **echo “\xFF” > /dev/ttyS0** on the linux box will light up one row of the led matrix.

Last but not least i took a [XMMS](http://www.xmms.org/) template plugin. Reworte it so the level output of the vu-meter is cutted down to 8 values. These values get sent to the PC’s serial interface.that’s it.

![AVR Matrix](http://optixx.org/images/avrmatrix/avrmatrix_s01.jpg)
![AVR Matrix](http://optixx.org/images/avrmatrix/avrmatrix_s02.jpg)

[Picture 1](http://optixx.org/images/avrmatrix/avrmatrix01.jpg)

[Picture 2](http://optixx.org/images/avrmatrix/avrmatrix02.jpg)

[Picture 3](http://optixx.org/images/avrmatrix/avrmatrix03.jpg)

[Source](http://optixx.org/download/avrmatrix.tar.gz)

[Binary](http://optixx.org/download/avrmatrix_bin.tar.gz)

One Comment

  1. Have a look @ blinkenarea.org

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