The third board for the inital set of boards is a CPLD based I/O board. The CPLD used in this design is an older Altera EPM7000S series. Hackaday readers might be familiar with this particular CPLD as it was covered in a series of articles( A Better Way to Plug a CPLD Into a Breadboard ). The CPLD is a 5V part which makes using a basic 5V power supply easy! I've added in 4 LEDs, 4 SinglePole-DoubleThrow (SPDT) switches that toggle between ground and +5V for basic logic levels. I've also included a 7 Segment LED and a pushbutton. To make programming the CPLD easy, a JTAG port was added that is supported with the inexpensive USB Blaster programmer that works with Altera's Quartus software. This board potentially could be used as a standalone development platform, so I added a barrel jack for power.