Go-6502 Emulator

$ Go-6502 Emulator

A cycle-accurate emulator for the MOS6502 and WDC65C02 8-bit microprocessors, written in Go. This project provides high-fidelity emulation of two classic 8-bit processors that powered many iconic computers and gaming systems.

install

go get github.com/andrewthecodertx/go-6502-emulator

### features

- Cycle-accurate execution — Faithfully reproduces timing behavior including page-crossing penalties
- Complete instruction set — All 56 documented MOS6502 instructions plus 27 additional WDC65C02 instructions
- All addressing modes — 13 addressing modes for 6502, plus 2 new modes for 65C02
- Hardware quirks — Implements the JMP indirect page boundary bug on MOS6502 (fixed in 65C02)
- Interrupt support — NMI, IRQ, and RESET vectors with proper handling
- Flexible bus interface — Pluggable memory system supporting RAM, ROM, and memory-mapped I/O

### usage

The emulator is designed to be embedded in your own projects. Add the module to your project and use either the MOS6502 or WDC65C02 CPU implementations.

Implement the Bus interface for your memory system
Instantiate your preferred CPU variant (mos6502.NewCPU() or wdc65c02.NewCPU())
Load machine code and call Step() or Run() to execute

### project structure

pkg/core/ — Shared components (BaseCPU, Bus interface, addressing modes)

pkg/mos6502/ — NMOS 6502 CPU implementation

pkg/wdc65c02/ — WDC 65C02 CPU implementation

docs/ — Documentation

### testing

go test ./... — Run all tests

go test -v ./... — Run with verbose output

go test -cover ./... — Run with coverage

### learn more

Full documentation, examples, and detailed instructions are available in the README.

GitHub → Documentation →