6502 CPU Emulator

A software emulation of the MOS Technology 6502 processor, a historically significant 8-bit microprocessor that powered iconic systems like the Apple II, Commodore 64, Atari 2600, and Nintendo Entertainment System (NES).

📑 Documentation

This project is documented across multiple files for better organization:

• Architecture - System architecture and component interaction
• CPU - CPU implementation, registers, and flags
• Memory - Memory organization and special regions
• Opcodes - Instruction set and addressing modes
• Demo Programs - Example programs and execution
• Testing - Testing framework and utilities

🚀 Quick Start

Prerequisites

• C++17 compatible compiler
• CMake 3.10 or higher
• Make

Building the Project

1. Clone the repository:

git clone https://github.com/your-username/6502_cpu_emulator.git
cd 6502_cpu_emulator

2. Build the project:

make setup
make build

3. Run the emulator:

make run

Running Tests

make test

📊 Project Status

The emulator currently implements:

• Basic CPU structure with registers (A, X, Y, PC, SP)
• Status flags (C, Z, I, D, B, V, N)
• Memory access with a 64KB address space
• Instruction implementations:
  • Load/Store operations (LDA, LDX, LDY, STA, STX, STY)
  • Subroutine handling (JSR, RTS)
  • Stack operations (PHA, PHP, PLA, PLP, TXS, TSX)
  • Jump instructions (JMP absolute, JMP indirect)
  • No Operation (NOP)

🔨 Development

The project uses CMake for building and testing:

• make setup - Configure the build system
• make build - Build the emulator
• make run - Run the emulator
• make test - Run the test suite
• make debug - Debug the emulator with GDB

📝 License

This project is open source and available under the MIT License.

🤝 Contributing

Contributions are welcome! Please check the Contributing Guide for details on how to get started.