A Microprogrammable Microprocessor Simulator and Development System

A microprogrammable microprocessor simulation is discussed. Four memory mapped I/O devices permit the interaction with various simulated on-line devices. The microprogrammable format, based on the architecture of the Am2900 family of bit-slice products, allows numerous architectures to be modeled. A development system that includes a microassembler and a macroassembler is detailed. The application of this simulation in teaching and the development and debugging of macro/ microprograms are discussed. The simulation is written in Pascal, and the assemblers are built using the UNIX development tools LEX and YACC.