CHIP-8 Emulator

Welcome to the CHIP-8 Emulator project! This emulator replicates the functionality of the CHIP-8 virtual machine, which was used in classic systems and is a popular starting point for emulator development. Below is a detailed explanation of the emulator, its capabilities, and how you can use it.

---

Table of Contents

1. About CHIP-8
2. Project Structure
3. Features
4. Getting Started
5. Usage
6. Development
7. References

---

About CHIP-8

CHIP-8 is a simple, interpreted virtual machine used to run small games from the 1970s. It features:

• A 64x32 monochrome display.
• A 16-key hexadecimal keypad.
• Simple instruction sets for drawing, input, and computation.

This emulator provides a modern implementation of CHIP-8 in Rust, suitable for learning and experimenting with low-level systems.

---

Project Structure

The project is divided into the following modules:

• cpu: The core logic for opcode decoding and execution.
• memory: Handles memory operations and fontset loading.
• display: Manages rendering and user interface.
• utils: Utility functions like random number generation.
• opcodes: Enum definitions for CHIP-8 instructions.

---

Features

• Instruction Set Implementation: Supports all original CHIP-8 opcodes.
• ROM Loading: Load and execute .ch8 ROM files.
• Emulation Cycle: Simulates the CPU cycle, including opcode fetch, decode, and execute.
• Graphics Rendering: Renders the 64x32 monochrome display.
• Timers: Implements delay and sound timers.

---

Getting Started

Prerequisites

• Rust installed on your system.
• A CHIP-8 ROM file to test (e.g., maze.ch8).

Installation

1. Clone the repository:

   git clone https://github.com/zerootoad/chip8-emulator.git
   cd chip8-emulator

2. Build the project:

   cargo build --release

---

Usage

Running the Emulator

1. Place your ROM file in the src/roms/ directory.
2. Start the emulator:

   cargo run --release

   This will load the default ROM (maze.ch8). You can modify the ROM path in the main.rs file.

Controls

Use the following keys for input (mapped to a typical keyboard layout):

CHIP-8 Key	Keyboard Key
1	1
2	2
3	3
C	4
4	Q
5	W
6	E
D	R
7	A
8	S
9	D
E	F
A	Z
0	X
B	C
F	V

---

Development

Key Files

• cpu.rs: Implements CHIP-8's CPU, including opcode execution.
• memory.rs: Handles memory management.
• display.rs: Implements graphical output.
• main.rs: Entry point of the application.

Adding Features

1. To add support for additional opcodes, extend the decode_opcode and execute functions in cpu.rs.
2. For graphical improvements, modify the display module.

Debugging

• Enable opcode logging by inspecting println! statements in cycle and execute.

---

References

• CHIP-8 Wikipedia
• Austin Morlan's CHIP-8 Guide

---

Enjoy building and experimenting with the CHIP-8 Emulator! Feel free to contribute or report issues on the GitHub repository. 😊