Designing my own 4x4x4 LED Cube. These are my working notes as I only spend an hour or so each day working on this.
Using the following:
2 x SN74HC595N shift registers daisy chained to give me 16 output ports from 4 digital ports on the Arduino.
1 x MC74HC138AN Decoder / Demultiplexer to switch the cathodes on the LEDs.
Info on the 595’s in serial can be found here: http://www.protostack.com/blog/2010/05/introduction-to-74hc595-shift-register-controlling-16-leds/
4 layers tall. Each layer has all LED Cathodes (-) connected to each other but not connected to any other layer. Each cathode layer will connect to it’s own pin on the MC74HC138AN. So 4 pins will be used on that IC in order to switch on or off a cathode layer. This allows us to selectively connect / switch on the negative to any one of the 4 independent layers.
16 vertical Anode columns. Each column of LED Anodes are connected vertically to the one below it. These vertical columns are independent of each other so we have sixteen vertical anode columns. Each column is connected to one output pin of the SN74HC595N ICs. Each IC has 8 outputs so we are connecting one anode column to each discreet output.
So by turning on one of the cathode layers and then turning on one of the positive anode columns we can light one of the 64 LEDs.