I am designing a RGB array. I am currently planning on using attiny2313s to control 4 RGB leds a piece. Each one basically running 12 software driven PWM channels, one for each R, G, and B LED.
I was thinking of hooking 25 or so of these 2313's up on the same UART. A master uC can send out a two byte message for every one of the 100 or so LEDs. One addressing the individual LED, and the other to specify a 256 value color.
The hardware UART and Interrupt on each of the 2313's will process the LED ID and ignore everything except for the 4 leds it is responsible for. If the message happens to address one of its leds it will process the second byte and set the PWM values accordingly.
My question is whether with the 2313's running around 16-20Mhz and the controller uC running at that or a little faster, can an array of 100 or 200 leds / 25 - 50 2313's can be refreshed at a reasonable rate. I'm not sure what Baud Rate that can effectively been achieved. If anyone has any comments or suggestions regarding anything that I talked about I would really appreciate it.