Mike, if you two want to fight, thats ok with me, but its not my interest., Im interesed in finding solutions, and some experimenting, and hopefully some learning and success.
I would like to know why something is a good idea, or a bad idea, so if you want to talk about what is good/bad about something and why, that is what im hoping to hear.
dhenry, Did you watch this video too, where he shows how he made them? I thought it was pretty impressive.
Im glad you like my shift registers, that is called piggybacking, its commonly used for building memory modules of different sizes, with one sized footprint.
I realized that it shouldnt matter if im using 5v or 3.3 on my other cube, since im syncing with the shift registers, they get 5 volts from the plane pin. I think i originally assumed you needed a resister on the anode side, not the cathode side, and I didtnt want to buy 16 resisters (they cost a quarter each locally...) So I made the cube common anode and used 4 resistors.
When I made the last cube, all the software I found was for common cathode, When I made this one, I made it CC, to avoid those problems.{fail}
Tom, wow 12cubed sounds awesome, is it RGB thats a heck of a lot of wires! and magnet wires has to be very difficult, I've soldered magnet wire, and its a pain in the butt to get the insulation off (I found tinning the end worked, but you have to burn alot of nasty insulation off, and its a lot of effort.
The wire Im using is 19 gauge galvanized wire (like bailing wire) for the anodes, and 24 gauge copper wire for the cathodes (since each LED requires 3 wires, I went with smaller gauge (less obtrusive, and the cube doesnt need that much structural support). I used the copper because I thought it would look good, and I could make the negative lines silver(color), and the positive lines copper)
The 19 gauge is good and stiff, it makes the cube fairly sturdy. Ive found that I spent a lot of time straightening the wire (it comes in rolls, but I want straight lines, and it takes a lot of effort to make the wire straight), I'd like to find straight wire, im considering welding/brazing rods.
Tell me about those TLC5951s and 5947s, im interested in finding PWM solutions for my common cathode cube. Its a 4x4x4, broken into 4 planes, I need to control 48 LED anodes (16 RBG), and 4 plane pins (cathodes). I could run the planes right from the arduino, or ??? The way i was originally planning on doing the matrix was with 4 Shift registers, 3 would control the cathodes, and 1 control the anodes. Now Im considering using 7 shift registers (6 for cathodes, 1 for anodes(1/2 really))
I dont understand the bit about decoders and p-ch mosfets, I did read something about someone hooking up a light strip that was CC, and they used something like that to make it work.
I did a lot of searching last night, and it looks like almost every RGB LED setup is CA, and I wasnt able to find any examples of CC RGB PWM LED drivers. Shift Registers are looking like a better approach right now.