MIME: An Educational Microprogrammable Minicomputer Emulator

This paper discusses the design and fabrication of MIME, a low-cost microprogrammable, general purpose computer specifically configured for use in an educational environment. In order to have utility as an instructional aid in the areas of computer control and microprogramming, such a machine must have the following high level attributes: educationally oriented human interface, educationally oriented design, and user microprogrammability. These attributes were employed as a basis for deriving functional and detail requirements. The AM 2900 bipolar microprocessor family was used as the basis for realizing the design which satisfied the defined requirements. The resulting hardware and software is being employed at the Air Force Institute of Technology by students in computer engineering classes and associated laboratories to investigate microprogramming and its application to emulation. The paper also presents, through the development of this processor, an excellent example of top-down design.