William's Homemade Computer

In order to pass FIU's one (1) credit lab for EEL-4746, you must build a computer from scratch using only discrete logic, I/O controllers, memory chips, and of course, a processor. This page is devoted to this time consuming project!

Some Quick Specifications:
  • Intel 486DX @ 20 MHz
  • Two 8251 Serial Controllers
  • Powered serial port to interface serial display
  • 8255 Parallel Port interfaced to 4 digit display
  • 8 channel Analog to Digital Converter
  • 32 KBytes RAM (expandable to 128 KB)
  • 32 KBytes EEPROM (up  to 128 KB)
  • Powered by single 5V supply
  • Draws 950mA with external display attached


Top view of the computer. The big chips on the left are the EEPROMS and RAM. The little chips are mostly control logic glue. The chips on the top are IO controllers.


VFD from MatrixOrbital next to computer. MatrixOrbital also sells the useful prototyping keypad seen in the bottom right.

Additional Pictures:

Top of board

Bottom of board

Top of board at perspective angle

Bottom of board at angle

Board next to display


The board has a lot of programming to go. It is programmed in assembly, and it's convenient that it is x86 assembly, since there is a lot of books and material written on it. Thanks for checking it out! Send me mail here.