A Processor Design Project For A First Course In Computer Organization

Although computers are part of our daily lives, students taking their first class in computer organization paradoxically often find computer design abstract and difficult to visualize. To make the material more tangible, we have developed a novel three part term project that requires students to develop and simulate their own processor. Students work in teams to devise and encode their own instruction set, design a datapath and microcontrol instructions to execute their instruction set, and simulate a model of their processor on a computer. While similar CPU design projects have been offered at other institutions, this project is unique for three reasons. First, it gives students freedom to be creative by letting them design their own instruction sets, while constraining them to practical limits by requiring them to encode their instruction set and compile a small program for it. Second, by building a simulator for their processor, students can actually see their processor run a program. Third, the project needs no special hardware or software, and does not require the students to have any extensive background experience either in digital logic design or programming. It can consequently be offered in programs that do not have access to specialized equipment, and is suitable for students across diverse disciplines. This project has been given to two classes of electrical engineering students and one class of computer science students at different universities, and qualitative feedback has been solicited. Students have universally expressed that this project has made the subject matter feel more tangible to them and has greatly increased their enjoyment of the course. Students have tended to take advantage of the design freedom given to them by experimenting with unusual instruction sets, and in one case a team actually built their processor in hardware. This paper describes the project itself in depth. It further discusses the student populations on which the project has been tried and the course contexts in which it was given. Finally, the paper looks at the student response to the project and the creativity of their submissions.