COMP 1500 Assembly Emulator

"COMP 1500: Computing Ideas and Innovation" is a course offered in the Department of Computer Science at the University of Manitoba.

In Fall 2017, we offered a unit where students wrote programs in a fictional assembly language. This is an emulator for that assembly language.

Building

make c1500

Running

The emulator expects programs to be written in plain-text files. Pass the plain-text file as the first argument to the emulator. Input for the program is provided on STDIN and output is written to STDOUT.

$ echo "1 2 3 4 -1" | ./c1500 test-data/prog.txt
10
$ 

Assembly

The assembly language has a very small number of instructions.

Instruction	Effect
SAVE address	Saves the ALU output to the specified memory address.
STORE value, address	Stores the literal integer value at the specified address
GETA address	Load the value from address into ALU register A
GETB address	Load the value from address into ALU register B
ADD	Instruct the ALU to add its operands
SUB	Instruct the ALU to subtract its operands
MULT	Instruct the ALU to multiply its operands
GETINPUT	Get input from the input device (the keyboard, STDIN)
OUTPUT	Write to the output device (STDOUT)
JUMP address	Unconditional jump to instruction at address
JUMPIFZERO address	Jump to instruction at address if ALU output is zero

The address space for instructions is separate from the data address space. That is, instructions that read and write from memory cannot read and write instructions.