Thanks for the speedy replies guys
Here's what I'm trying to do...
I have an Arduino Uno R3.
I have some indicators that display a number from 0 to 9, depending on which one of 10 wires is powered.
I want to stack 6 of these together to create a 6-digit display.
With 10 inputs per digit, 6 digits would need 60 wires. If I use a BCD-to-decimal decoder, I can get away with 4 wires per digit, but that still takes up 24 digital outputs on the Arduino.
If I buy a Mega, I can make it work, but I was hoping to do it with my Uno somehow.
I'll do some reading on the 595 Shift registers, and the LED bar graph chips to see if they can do what I need... Thanks again!