I have to admit using a CPLD for the I/O Module feels like a bit of a cheat, but I already had this design completed as part of the Digital Design Doohickey project. I hope to replace this with something more appropriate later on down the road. The design includes some LEDs for display the data that is currently being presented on the 4-bit Data Bus. The CPLD is directly connected via the I/O pins to a 7-segment display, 4 LEDs, 4 switches, and a push button. The CPLD is programmed via a 2x5 JTAG header on the board. The Altera EPM7064SLC44-10N is a costly part (around $9.00USD at digikey), and is a End-of-Life project. I already had some on hand, and the board was already designed, so I decided to use it for now.  The design is loosely based around a post made on a Hackaday a while back called "A Better Way to Plug a CPLD Into a Breadboard".