It’s been a while since my last post, so I thought I’d share what I’ve been up to. I am currently working with 8×8 LED Matrices to show images and patterns. I have 2 going right now on a breadboard, but my goal is to design a controller board for each matrix so that arrays can be snapped together to form big panels.
There is a good tutorial on how these matrices work here, including a good schematic. Keep in mind that there at 8×8 LEDs x 3 color diodes, so 192 individual diodes. Thankfully, all of the cathodes of a given color are common per row and all of the anodes of all diodes are common per column. This simplifies the number of pins down to 8 rows of red + 8 rows of blue + 8 rows of green + 8 columns = 32 pins.
They require a driver chip and I am using the TLC5947 on a breakout board from Adafruit, although there are many possibilities for this.