The following machine description will provide the basis for this assignment. You will create a virtual machine/operating system for the machine described below that will accept programs in the target machine language. The details for this assignment are presented below following the machine description.

Project Description

Design and implement a program to simulate the operation of the SIMMAC based on the descriptions above.

Add a HALT instruction that dumps the contents of all registers and memory and then prints an "End of Job" message.

Your project must implement multi-tasking in a single queue using a round-robin scheduling discipline. You will implement process entities (jobs) that will allow your machine to run several SIMMAC machine-language programs. In order to do this you will define a Process Control Block (PCB) data structure that will be created for each job in your system. For this assignment assume each SIMMAC instruction is equivalent to one clock cycle. Additionally the time quantum value for round-robin scheduling is an integer multiple of a clock cycle. The quantum value is to be set on the command line or prompted for during initialization.

You will define the notion of an interrupt handler that will process a time quantum for each running job. On each job switch, you will print some state information such as which job will be loaded and the current state of the job queues.

Your version of SIMMAC will then run multiple SIMMAC machine language programs simultaneously. These programs will test the ability of your SIMMAC to handle multitasking and scheduling. You must design your system such that all SIMMAC machine programs are loaded from text files.

The SIMMAC must be designed to take command line arguments or to prompt for input files in addition to the previously specified items. By this mechanism, all SIMMAC language programs will be loaded. Since there is the LDI command, all data can be loaded into SIMMAC memory using SIMMAC programming statements.

You must develop the following SIMMAC language programs to be run on your SIMMAC machine:

1) Write three programs in the machine language of the SIMMAC that will total the numbers stored in 20 different locations and place the result in a single location.

2) Write a program in the machine language of the SIMMAC that will decrement the value stored in location 201 (must be at least 100) by one until the result is zero. Store the result in location 202.

3) Write a program in the machine language of the SIMMAC that will increment the value stored in location 301 by two until the value has been increased by 200. Store the result in location 302.

Opcode Operand

You will be responsible for turning in the system design document, source code of your version of SIMMAC (this code must be appropriately commented & readable), an executable version of your SIMMAC, and the output generated from your SIMMAC programs running on your version of SIMMAC. These items are to be placed in ZIP format and submitted to the OS Problem Set Assignment in Blackboard Assignments.