LED prism project questions (noob warning)

So for my first larger arduino project I’d like to create a 16x6x6 LED prism. So by my count that’s (6x16 anodes)+6 cathode levels = 102 needed outputs. Or now that I’m writing it down I see that it would probably make more sense to do (6x6)+16 = 52… anyway
My first question is, will the arduino uno have any trouble handling the current needed to light all 576 LEDs?

My initial tentative plan would be to use 12 flip-flops (I have some SN74HC574Ns). So that’s 12+8 outputs to control those, plus the 6 for the LED cathode levels. To get those 26 I thought I’d use three 3-8 line decoders (I have some M74HC138B1Rs).
That would be (3x3)+2 = 11 arduino output pins.
My second question is does that make any sense at all, am I on the right track, and could that work?

will the arduino uno have any trouble handling the current needed to light all 576 LEDs?

Basically no, but you will not be powering it from the arduino but from the chips attached to it.

My second question is does that make any sense at all, am I on the right track, and could that work?

It could but the usual way of doing this would be to use shift registers and software like this.
http://www.elcojacobs.com/shiftpwm/

Thanks, the shift register approach does seem better/more straight forward.

So what's powering the chips; I need an external power source? Is there a standard recommendation to use for that?

The shift register chips can be powered from the 5V output line on the arduino but this is limited to 500mA if powered from the USB or about 600-800mA if powered from an external source. It depends on the input voltage applied to the jack. Otherwise an external regulated 5V supply is needed. There is no standard one to use.

Grumpy_Mike:

will the arduino uno have any trouble handling the current needed to light all 576 LEDs?

Basically no, but you will not be powering it from the arduino but from the chips attached to it.

Love that answer!

In short, you will need a separate power supply.

I am wondering why you chose 16x6x6 rather than 16x8x8. "6" is not very binary.

I have become fond of MAX7219s - they do all the work for you and can drive plenty of current.

They are capable of a multiplexed 8 by 8 display but you can limit the scan register to six columns for a 1 in 6 multiplex instead of a 1 in 8. That would require sixteen of them for 16 planes of 6x6. If however, you are prepared to do some slightly fancy wiring, you can "fold" the extra columns into successive planes and you only need twelve such chips. (The coding to do this turns out to be dead easy.)

Paul__B: I am wondering why you chose 16x6x6 rather than 16x8x8. "6" is not very binary.

I want it to be fairly "long"; I intend to use it to display text. While the non-binarity may not be as nice from the build aspect I think it will be better aesthetically. And it means fewer LEDs that I need to solder.