Huge LED Driver or Microcontroller

Hello,

I need a microprocessor that can handle sending out information to several microcontollers.

Basically I need to be able to individually control over 11000 RGB LEDs. For a scrolling message to work i’d have the microprocessor figure the display and send a basic amount of info to a microcontroller that would handle the distribution of the signal to the correct leds that is in a 12x12 matrix. I need about 80 of these boards to cover a 10x8 foot area on the wall. Any ideas?

I would love to have this on SFE considering everything else I need is there.

SPI, TWI, I2C, RS232

Lots of ways for standard microcontrollers to communicate.

Lefty4000:
Any ideas?

Yes but probably not a good one ! :mrgreen:

Instead of using 80 of your matrix boards, you could use 180 of [these (or really just the backpack portion) and arrange them in a 15 x 12 matrix, where each backpack controls an 8x8 set of RGB LEDs (as opposed to your 12x12 set). I believe each backpack can be daisychained though I’ve not bother to work out what the timing would be to update 180 of them. :shock: You might have to divide that task up. Of course the cost in now at least 2X what it could be if you had a 12x12 controller … but you did ask for any ideas.

FWIW I doubt enough of your 12x12 matrices would be sold to justify the investment by SF. But that needn’t stop you from mutating the design above into what you need.](http://www.sparkfun.com/products/760)

I’m not exactly looking for a communication, I can figure out the comm out, its the microcontroller i need to figure out. I need one that can handle that kind of load.

XMOS devices are used for large LED displays:

http://www.xmos.com/applications/led-signs-and-displays

Doesn’t seem that hard to do it with a single MCU and a bunch of shift registers.

You want to control 80 12x12 matrices of LEDs. If you use two 8-bit shift registers each for row & column addressing on each board, and two 8-channel source and sink drivers on on the rows & columns, that’s only a total of

80 x 32 = 2560 bits for each update. If you are using high efficiency LEDs you may not even need the drivers.

Assuming you update all the LEDs at a 24Hz rate to avoid flicker, then that’s 24x2560 = 61.4kHz update rate. You can bit bang that with a 1MHz microcontroller. A 75Hz rate would be even better and it’s still doable in software. I’d consider using a synchronous serial output to avoid having to bit-bang, but that’s an implementation detail.

[edit]

corrected my math.

what is bit bang?

Manually toggling bits…i.e. doing serial communications by twiddling bits high and low and calculating the timing “manually” vs. using a built in UART module.

http://en.wikipedia.org/wiki/Bit_banging

Amazing…

Oh, I think tahts all I know how to do. haha