Microprocessor controlled microprogramming education system

Abstract

A significant trend in computer design in recent years has been the replacement of the hardware control section by a microprogrammed control. The main reason for this shift is the inherent flexibility of a microprogrammed computer and also its economic superiority over the conventional hardware control implementation. To understand and apply the method of microprogramming is somewhat delicate and difficult, so there is need of some educational tool of microprogramming technique. Software simulators has been widely used either to understand the operations of micro-codes or to validate the correctness of the produced micro-codes. In this thesis a microprocessor controlled microprogramming education system (MCMES) is proposed. MCMES is a system of hardware and software integration. Hardware consists of a microcomputer system with user programming facilities, a microprogrammable system, for which micro-codes are to be educated, and an interface. Software consists of a microassembler and dynamic a microprogram debugger. For the implementation of MCMES, An Altair 8800 with diskette drives and a serial I/O device is used as the control processor and a user microprogrammable machine (UMM-1) is designed using AM 2900 family. An interface for this system is also implemented. For the software facilities of MCMES, ASM29 and DMD 29 are also developed. For the purpose of cost saving and for the convenience of dynamic debugging, UMM-1 utilizes the main memory of the Altair 8800 for mapping ROM and control memory. In addition, the feature that allows machine instructions of UMM-1 can be freely defined, is implemented on MCMES. Finally, several experimentations are made to show how to use MCMES.