DESIGN AND IMPLEMENTATION OF A MULTILAYERED MONITOR FOR AN 8085 BASED MICROCOMPUTER - A STRUCTURED APPROACH•

Abstract

The profound changes in computer hardware technology due largely to the introduction of the Microprocessor are having a strong impact on software engineering techno-logy. A need was felt to use one of the most sophistica-ted programming tools i.e. STRUCTURED APPROACH to develop the heart of the system software which goes with any modern day Microcomputer viz. Monitor. This enables one to have, at his disposal, a MULTILAYERED MONITOR far more readable, highly modifiable and modular than its contem-poraries based on tradition,. programming techniques. This thesis is an effort in this direction to accomplish the task to the extent possible. As a part of this thesis, a multilayered monitor has been designed and implemented for an 8085 based system. The design philosophy of the present problem is quite different end has been divided into different phases. In the very first phase of design, tasks to be performed by monitor for a general or particular problem were defined. Next phase was to choose a particular system with all necessary hardware requirements for which various operations are controlled by the monitor. The software routines both necessary/optional were planned in such a manner that.a layer dependency could be achieved i.e. software routine of a particular level calls its previous levels routines necessary to perform the required task. Keeping this point in mind a layered structure of different routines were designed. After designing, - software routines were tested on 8085 based system so as to 1 tnk them layer-wise in order to perform .monitor func-tions automatically. A Multilayered Monitor of 12 layers with various software utility routines has been designed and implemen-ted. The matter embodied in the following chapters is an attempt to present the user with a complete and com-preherisive methodology on how to design .rxnitor for a particular environment.