assembler and simulator

This project is a simple simulator and assembler for a hypothetical assembly language, created as part of the CSE 112 - Computer Organisation course. The project includes functionality to read assembly code from a file or standard input, parse and translate it into machine code, and handle various errors that may arise during the process.

Features

Assembly Code Input: Accepts assembly code through a text file or standard input.

Error Handling: Checks for syntax errors, invalid immediate values, undefined variables/labels, and other common issues.

Binary Code Output: Translates assembly code into binary machine code and outputs it to a file (output.txt) and the terminal.

Simulation: Simulates the execution of the assembly instructions.

Instructions

Input You can provide the input assembly code in two ways: Standard Input: Uncomment the following lines in the script to read input from standard input:

import sys code = sys.stdin.read().splitlines() Text File: Provide the path to the text file containing the assembly code and uncomment the following lines:

with open('t.txt') as file1: code = file1.read().splitlines() Output The output binary code will be written to output.txt and also displayed in the terminal. Ensure you have write permissions for the directory where the script is located.

Running the Script

Ensure all dependencies are installed:

No external libraries are required. Make sure Python is installed on your system.

Execute the Script:

If using standard input, run the script and provide the assembly code input directly. If using a text file, ensure the file path is correct and run the script.

Error Handling

The script performs extensive error checking, including:

Invalid immediate values (non-numeric or out of range). Invalid register names. Undefined variables or labels. Multiple declarations of variables or labels. Missing hlt instruction or hlt not at the end. Illegal use of the FLAGS register. Sufficient parameters for each operation. If any errors are found, the script will print an appropriate error message and terminate.

Code Structure

The script is divided into the following main sections:

Input Handling: Reading assembly code from either standard input or a text file.

Data Structures:

RegAddress: Maps register names to their binary codes. operations: Maps operation mnemonics to their binary opcodes and instruction formats. labels, var: Lists to store labels and variables.

Error Handling: Checks for various types of errors in the assembly code.

Assembler Logic: Parsing the assembly code and converting it into binary machine code. Handling labels and variables appropriately.

**Output: ** Writing the generated binary code to output.txt and displaying it in the terminal.

Example

An example of an assembly input file (t.txt): assembly var x add R1 R2 R3 mov R4 $5 st R1 x hlt

To run the script with this input file, ensure the following lines are uncommented in the script:

python with open('t.txt') as file1: code = file1.read().splitlines() Execute the script and check output.txt for the resulting binary code.

Group Members

Aditya Sharma (2022038) Ayan Kumar Singh (2022122) Ayaan Hasan (2022121) Kanishk Kumar Meena (2022233)

#License This project is created for educational purposes as part of the CSE 112 course. Feel free to use and modify it for similar educational use cases