Simulating and compiling a hypothetical microprogrammed architecture with projects for computer architecture and compiler design

Abstract

3 8 .Introductio n Many of our computer science courses involve teaching students about rather large and complex hardware and/o r software systems . While we would like our students to retain th e important concepts in such courses, we also would like them t o have "hands-on" experience which will ensure better understanding of the concepts as well as better appreciation for th e complexity of the systems . Unfortunately it is not alway s possible to do this within the time constraints of a one semester course .For this reason, many courses involve simulations o f hypothetical machines or simplified software developmen t projects . Hands-on projects involving the simplified systems and explanations of how actual systems may differ from th e simplified systems combine to provide the student with a fir m understanding of the concepts.In this paper we deal with a fictitious architecture take n from [Tanenbaum 1990] and show how it can be used to provid e students with laboratory projects in two courses : Compute r Architecture or Organization, and Compiler Design .We will deal in particular with the microprogrammin g level of a fictitious machine called "Mic 1 " since the complexity , parallelism, and interconnectedness of actual microprogramme d computers are not appropriate for a first undergraduate course i n Computer Architecture . This paper describes a software simulator for the Micl architecture and proposes several projects for students ranging from simple Micl programs to the simulator itself as a project . Students gain a better understanding of thi s architecture and retain more concepts as a result of programming and debugging algorithms for the Micl machine .We will also deal with a high-level like language calle d MAL which is used to program the Midi machine . Thi s language is sufficiently similar to Pascal that its implementatio n serves as an appropriate project for a first undergraduate cours e in Compiler Design . Students who are enrolled in both Corn-SIGCSE Vol . 25 No . 2 June 199 3 BULLETIN puter Architecture and Compiler Design at the same time ca n benefit by applying concepts from one course to another .[Moore 1983], [Parker 1984], [Donaldson 1987], [Fole y 1992], and others have reported on the use of a simulator fo r microprogramming projects . This work is different in that i t also makes use of a compiler for a high level language used t o program the microarchitecture, enabling students to tackl e problems of much greater complexity, such as an interpreter fo r a conventional machine . 2.The Micl Architecture A. The Mic 1 Data PathThe Mic 1 architecture, as specified in [Tanenbaum 1990] is a 16 bit architecture consisting of 16 general purpos e registers (each 16 bits wide), a 4 function ALU, a shifter, a 64 K x 16 bit RAM, and a 256 x 32 bit control store. The data paths are 16 bits wide and are shown in figure 1 , B. The Microinstruction Forma tThe control store is 32 bits wide, allowing for 32-bi t microinstructions . The microinstruction format is describe d below, in order fr...

A microprogram simulator and compiler for an enhanced version of Tanenbaum's MIC-1 machine

“…In most cases, however, access to microprogrammable hardware is not available. Although some instructors have utilized commercially available microprogrammable processors [1] or actually built microprogrammable hardware for classroom use [2], the most common approach has been to rely on software simulation of hardware at the microprogramming level [3][4][5][6][7][8][9][10][11][12]. The simulation approach allows students to carry out a variety of exercises involving the implementation of a conventional machine language.…”

A microprogram simulator and compiler for an enhanced version of Tanenbaum's MIC-1 machine

“…In most cases, however, access to microprogrammable hardware is not available. Although some instructors have utilized commercially available microprogrammable processors [1] or actually built microprogrammable hardware for classroom use [2], the most common approach has been to rely on software simulation of hardware at the microprogramming level [3][4][5][6][7][8][9][10][11][12]. The simulation approach allows students to carry out a variety of exercises involving the implementation of a conventional machine language.…”

Architecture Abstraction As An Aid To Computer Technology Education

“…Mainstream computer science education is well supported by journal articles on various aspects of re-programmable hardware for educational purposes 6 and assembly language 7 . Simulation has proved to be a very useful tool 8,9,10 . Reid used laboratory workstations to allow undergraduate students to "build a complete, functioning computer -in simulation" 11 .…”