Software-Defined Computer with a Classic Microprocessor

The paper describes the concept and the design process of a software-defined computer built for didactic purposes and as a proof-of-concept. The computer uses a classic microprocessor from the 1980s with all of its other components – memory, I/O, supplementary glue logic and a hardware bus monitor implemented with a contemporary mainstream microcontroller with Cortex-M family core. The concept of a software-defined computer was successfully implemented with four significantly different microprocessors. The computer may be used for illustrating the operation of a processor and for teaching the basics of low-level programming. It is also capable of running CP/M operating system. Its operation is controlled at both hardware and software level from a PC via two instances of a terminal emulator software.