[![saythanks](https://img.shields.io/badge/say-thanks-ff69b4.svg)](https://saythanks.io/to/irmen)
[![Build Status](https://travis-ci.org/irmen/ksim65.svg?branch=master)](https://travis-ci.org/irmen/ksim65)

# KSim65 - Kotlin/JVM 6502/65C02 microprocessor simulator

*Written by Irmen de Jong (irmen@razorvine.net)*

*Software license: MIT, see file LICENSE*


![6502](https://upload.wikimedia.org/wikipedia/commons/thumb/4/43/KL_MOS_6502.jpg/320px-KL_MOS_6502.jpg)

This is a Kotlin/JVM library that simulates the 8-bit 6502 and 65C02 microprocessors,
 which became very popular in the the early 1980's. 

Properties of this simulator:

- Written in Kotlin. It is low-level code, but hopefully still readable :-)
- Designed to simulate hardware components (bus, cpu, memory, i/o controllers) 
- IRQ and NMI simulation
- Aims to be clock cycle-precise (not yet 100% correct right now) 
- Aims to implements all 6502 and 65c02 instructions, including the 'illegal' 6502 instructions (not yet done)
- correct BCD mode for adc/sbc instructions on both cpu types   
- passes several extensive unit test suites that verify instruction and cpu flags behavior
- maximum simulated performance is a 6502 running at ~100 Mhz (on my machine) 

## Documentation

Still to be written. For now,