MOS Multiprogramming Operating System

This project implements a Multiprogramming Operating System (MOS) in three phases, gradually adding complexity and functionality. It simulates how jobs are handled by the system, including input/output management, error handling, and memory paging. Each phase builds upon the previous one, starting with basic execution and moving toward more advanced features like multiprogramming.

Table of Contents

• Project Overview
• Phase 1
• Phase 2
• Phase 3
• Installation
• Usage
• Contributors

Project Overview

This project simulates an Operating System that evolves over three phases, each improving the system's ability to handle multiple jobs and manage resources. The project is built in a modular manner, allowing you to see how the system grows from simple, single-job execution to a robust multiprogramming environment.

Phase 1

Phase 1 represents the simplest form of MOS, focused on executing a single job at a time without any multiprogramming features. The goal of this phase is to establish the foundational functions of the system:

Key Features:

• Single Job Execution: Only one job is loaded and executed at a time.
• Job Input (Card Reader): Jobs are loaded from the Card Reader into Main Memory starting at address 00.
• Instruction Execution: The CPU fetches and executes instructions in sequence, including Load, Store, Compare, and Branch.
• Interrupt Handling (SI):
  • SI = 1: Read from the Card Reader.
  • SI = 2: Write to the Line Printer.
  • SI = 3: Terminate the job after completion.
• Job Completion: Once the job is finished, the system clears memory and resets for the next job.

This phase provides a basic fetch-execute cycle without multitasking or error handling.

Phase 2

Phase 2 introduces more advanced features like multiprogramming, error handling, and memory management. It builds upon Phase 1 by adding significant capabilities:

Key Features:

• Basic Multiprogramming: The system now supports loading and managing multiple jobs concurrently.
• Paging Mechanism: Memory is managed using paging with a Page Table Register (PTR) for efficient memory access and protection.
• Advanced Interrupt Handling:
  • PI (Program Interrupts): Handles errors such as invalid operations.
  • TI (Timer Interrupts): Enforces time limits to ensure jobs don’t overrun.
  • SI (Service Interrupts): Manages input/output, similar to Phase 1.
• Error Handling: Includes mechanisms to manage system errors and job failures.

This phase introduces more sophisticated memory and job management, allowing the system to be more efficient and stable.

Phase 3

Phase 3 continues to build on the system's capabilities with more complex scheduling, resource allocation, and protection mechanisms (if applicable). More details can be provided once this phase is implemented.

Installation

To run the MOS project locally, follow these steps:

1. Clone the Repository:

   git clone https://github.com/Swapnilpatil03//MOS-Multiprogramming-Operating-System-

2. Navigate to the Project Directory:

   cd Assignment_intern

3. Run the Program: Instructions for running the different phases of the system will be added here.

Usage

• Phase 1: Demonstrates how a single job is executed in the MOS environment with basic I/O handling.
• Phase 2: Shows multiprogramming and error handling in action.
• More detailed usage instructions for each phase will be added as the project progresses.