In this project series, I build an 8-Bit Computer from 74 series logic. I start with the ALU.
Warning: This tutorial series is under-documented and the videos are incomplete. I stopped documenting this project half way through the summer of 2014 because I was in a rush to finish this before I left for MIT. Either way, get what you can from these and feel free to contact me if you have any related questions.
God, I don't know why I filmed this video. I am so sorry for making you watch me stick wires in a breadboard. Anyway, here it is... the construction of the ALU on a breadboard.
In this video I present the completed ALU... on a breadboard.
In this video, I discuss how to perform subtraction on the ALU using the Two's Complement scheme.
Here I go over the construction of circuit for performing the Two's Complement scheme. I then demonstrate some addition and subtraction on the ALU... I presume. I haven't actually seen this video in 6 years ;P
In this video, we get to the interesting topic of registers and how to store data in a computer.
This video is an awesome demonstration on our register storing data. It was a lot of fun for me to actually see this digital circuit working. I hope you enjoy it as much as I did!
In this tutorial, we develop a scheme to multiplex between our 16 registers. I then demonstrate this concept on a stack of 16 register PCB's. Sorry guys, the documentation ends here.
After tackling this project, I feel as if I have a firm understanding on how finite state machines work. All a computer is is a device that passes data between registers on a clock. The data can be manipulated and mutated along the way (known as combinational logic,) but regardless, data is simply being passed between registers on a clock.
Sorry this documentation is incomplete. What you want to look up in order to finish the computer is something called the control matrix. The control matrix is just a big, complicated multiplexor that looks at each piece of memory stored and decides what to do based on what instruction that memory - the op code - dictates.
I hope you enjoyed what is documented of this series. Maybe I'll get around to building an updated version someday.
Bunch of Electricals | Matthew Ian Burns
burns.matthewian@gmail.com