Incompatible Timesharing System

An Operating System for Z80 computers, written in assembly

Fully documented and annotated source code for the cassette version of Elite on the BBC Micro

An open source sort-of CP/M 2.2 distribution.

Original sources and binaries for Supermon+64 V1.2 by Jim Butterfield

Proto Language AsSeMbler for All (formerly Apple)

Disassembly of the Apple II Desktop - ProDOS GUI

A Z-machine interpreter for the Commodore 64 and similar computers

A Z80-based homebrew computer withTMS9918, AY-3-8910, Z80 CTC, Z80 PIO, and Z80 SIO

Fully documented and annotated source code for Elite on the Nintendo Entertainment System (NES)

A modern, scratch-built, open-source (GPLv3) alternative ROM BIOS for PC, XT, 8088 Clone or Turbo PCs.

C64 Christmas Demo in 6510 Assembly

This is a reconstruction of the original 1981-82 IBM PC BIOS source code using scanning and transcription of the BIOS listings found in the IBM Technical Reference manuals.

SDL-based Nascom 2 emulator

6809 and OS-9 emulator in Java

Fully documented and annotated source code for Aviator on the BBC Micro

CP/M for the Commodore 128

An interface for the DCD protocol used by Apple's Hard Disk 20.

SE BASIC - A free BASIC interpreter written in Z80 assembly language

A 6502-based Commodore 64 assembly language repo for OSX and Ubuntu. This is a very small and targeted OSX and Ubuntu port based on the original work of Chibi Akumas as the sole purpose of this small repo is to help you port Chibi's work to OSX or Ubuntu and nothing more. For more detailed 6502 tutorials please visit https://www.assemblytutorial…