A simulator for microprogramming

Microprogramming is a complex area for students to master because it involves integrating knowledge of a machine language, a microprogramming language and the design of a microprocessor. A software simulator for microprogramming is valuable because it provides an opportunity for the student to test and debug microprograms, and thus, to gain laboratory experience in this field. A microprogramming simulator is an especially fitting topic, because simulation is a primary application of microprogramming.

To provide a simple setting for students to gain experience in microprogramming, a 16 bit microprocessor was designed utilizing bit slice technology. Bit slice devices are fourth generation LSI building blocks for digital design, that have been specifically developed for use in microprogrammed systems. A machine language and a microprogramming language were defined and assemblers were written for each language.

A software simulator program was written to execute a machine language program, utilizing the microprograms written by the student. A simple debug function allows the user to step through the execution of the program and to examine current values for variables. The output of the execution is the content of the machine registers and the main memory.