Currently been working on a shield based on a Max 7219/7221 chip to control an array of LED’s with the same logic used in the arduinome chip. My thinking is this could be a sort of EQ board or an expanded led array that attaches directly to the arduino. programmed for many uses but mainly because I wanted to make something that was similar to the materials of a arduinome board.
there is the schematic, the board itself is changing all the time as i try and get the traces right. The board itself is open source so you can develop on it. let me know if you want the brd or sch file and I will upload them. until then, I am going to try to make sure everything is right, then order the parts and pcb’s
so far an average cost for making this is about $0.50-$0.80 per LED (times 64) unless you can find cheaper costs. the LEDs are of the package size is 1206 and prices are quoted from digikey. Unless of course Seeed could pick up some blue smd 1206 LED’s heh. the capacitors are also 1206 package smd as well as the max 7219cwg which is the soic24 version. I am also using the Arduino-Various.lbr library from here for the arduino shield schematic. a total cost is around $40-45 depending on where you get your max chip. and thats of course before you buy the pcb since it takes so many LED’s.
I am not experienced in this so if you see issues, please let me know because I am going off of white papers and forums and googling.