Implementation of the projects on http://www.nand2tetris.org/
The purpose of this project is to build a general purpose computer (hardware and software stack) from first principles.
The following is a detailed diagram of the Hack CPU, the CPU design used in this project.
A diagram of the computer is shown in this diagram, taken from The Elements of Computing Systems by Noam Nisan and Shimon Shocken.
These projects were implemented by David Brenner (http://www.david-brenner.net). Questions should likely be directed towards the authors of the course at http://www.nand2tetris.org.