I have been doing some tests with the ShiftMatrix library (http://arduino.cc/forum/index.php/topic,66988.0.html) from ElcoJacobs. The latest version seems to be stable and good for a purpose I have been working toward. I have been working on making a LED Video Display for a christmas display. Originally I was basing it on the Peggy 2.0 design from Evil Mad Scientists. This allowed 25x25 monochrome. I even managed to make a processing sketch to feed it video from a windows computer (I don't have Mac). This was good but I wanted bigger/better. Hence this thread.
I have Elco's library working, giving me 16x48 LED's with 32 levels of brightness. This is currently Monochrome. I want to go RGB. So 48/3=16 giving me 16x16 RGB. But I want bigger than this. I have seen many people wanting to accomplish big things with the Arduino and the comments that go with them tend to be similar in that they say "Make it Modular". So if I make a 16x16 RGB section with LED drivers and accompaning Arduino as one module, with 4 modules I could have 32x32 RGB Matrix with 32 levels of brightness.
This is all theory at this stage, I only have 1 breadboarded prototype. My next question is how to get the frame data to the devices? And can I do it at say 15fps. At 32x32 thats 1024 RGB LED's. Thats 3072 individual LED brightness levels. Sending each LED's level as a byte is 3072 x 8= 24576 bits. Thats for 1 Frame, 24576 x 15 = 368640 bps. Thats just the data, not sure what the overhead would be?
My first thought was to use I2C. This would mean using a seperate Arduino as a usb -> I2C master. Or I could use serial, linking all the Rx pins togther. I would need start and stop headers for each module and all data would be sent to all micros but they would only act on the data with their header.
I suppose I am asking if all this is feasable or am I just aiming too high? Also I am sorry for the cross post about speed/interfacing. I will keep it all here as the project is actually about a LED matrix.