Emulators: prospective instruments for instruction in systems programming

Microprogramming is a technique for implementing machine language instruction sets --it is critical in today's computer architectures and operating systems. An emulator is a set of microprograms that implements the architecture of one machine on another; microprogramming is often used in emulation to make one computer system appear as if it were another. This paper presents the architecture for a microprogrammed computer system, the VSEM. The simulated virtual computer system, its monitor and a simulated concurrent PASCAL are discussed. The usefulness of the VSEM, its monitor and the concurrent PASCAL as vehicles for instruction in systems programming is addressed.