Experience with a high level micromachine simulator

Abstract

As part of a microcoding project, we developed a simulator that offers a relatively high level view of a micromachine. The simulator supports all out a few features of the hardware, and provides a more friendly environment for the microprogrammer. In addition, the simulator supports a number of microprogramming conventions at a level inaccessible to the hardware. The simulator was implemented in a high level language, which contributed to its timely delivery and flexibility and did not detract from its efficiency. The simulator has been used to validate all of our microcode, with considerable success. Over 98% of microcode bugs have been found during simulation. The credibility of our microcode by the time it reaches hardware has also improved the detection and correction of hardware bugs.