64tass: This is the manual for 64tass, the multi pass optimizing macro assembler for the 65xx series of processors. Key features: Open source portable C with minimal dependencies - Familiar syntax to Omicron TASS and TASM - Supports 6502, 65C02, R65C02, W65C02, 65CE02, 65816, DTV, 65EL02, 4510 - Arbitrary-precision integers and bit strings, double precision floating point numbers - Character and byte strings, array arithmetic - Handles UTF-8, UTF-16 and 8 bit RAW encoded source files, Unicode character strings - Supports Unicode identifiers with compatibility normalization and optional case insensitivity - Built-in “linker” with section support - Various memory models, binary targets and text output formats (also Hex/S-record) - Assembly and label listings available for debugging or exporting - Conditional compilation, macros, structures, unions, scopes.

8FORMAT: This is a follow-up to my previous article about connecting old 8″ drives directly to a PC equipped with a classic floppy disk controller. Since there is a way on how to do it on a hardware level without paid or proprietary equipment, there still needs to be a free and available software solution that enables the OS to interface these drives, as they were not officially supported on the PC during its entire history whatsoever. So, during my experiments, I’ve came up with one: 8FORMAT – a small software bundle that’s also released open source.

A/UX Server Penelope: Between the years 1987 and 1995, Apple Computers, Inc produced a distribution of Unix for the 680×0-based Macintosh. Based on System V release 2.2, Apple Unix (A/UX) provided a familiar Macintosh Finder environment with the ability to run both Unix and Mac applications. While the two products share no code, A/UX was the “conceptual ancestor” of OS X.

Apollo-11: Original Apollo 11 guidance computer (AGC) source code for Command Module (Comanche055) and Lunar Module (Luminary099). Digitized by the folks at Virtual AGC and MIT Museum. The goal is to be a repo for the original Apollo 11 source code.

ArchiveOS: Archive of Operating Systems mission is saving the great job of many great people whose created Open Source and/or Freeware distributions/operating systems. The systems we archive are based on Linux, BSD, DOS, Solaris, and other, independent technology.

BASIC Computer Games: We’re updating the first million selling computer book, BASIC Computer Games, for 2022 and beyond!

BassoonTracker: Webbased old-school Amiga music tracker in plain old javascript - Plays and edits Amiga Mod files and FastTracker XM files.

Classilla: Building a Secure Web Browser for Mac OS 9 and the Classic Macintosh OS.

Commodore Source Code: This repository collects the original source code of various Commodore Business Machines (CBM) computers converted to a modern encoding (ASCII, LF, indentation). Using kernalemu and cbm6502asm, almost all source in this repo can be built from the UNIX command line. To build everything, run build.sh from the Unix command line, on a case-insensitive filesystem.

CP/M-80 at Foxhollow

CP/M Callback Filesystem: cpmcbfs is the use of the EldoS Callback Filesystem library, combined with the cpmtools project by Michael Haardt, to allow Windows to mount CP/M filesystems.

CP/M Filesystem in userspace: cpmfuse is the combination of the FUSE project by Miklos Szeredi (delivered with most modern Linux distros), and the cpmtools project by Michael Haardt.

CP/M for OS X: It… allows you to run CP/M-80 software on your Mac - supports drag and drop mounting of drives for opening files - supports copy and paste - uses native text rendering for a completely flexible window - multitasks, naturally.

CP/Mish: CP/Mish is an open source sort-of-CP/M distribution for the 8080 and Z80 architectures (although for technical reasons currently it only works on the Z80). It contains no actual Digital Research code. Instead, it’s a collection of third party modules which replicate it, all with proper open source licenses, integrated with a build system that should make it easy to work with.

Demozoo: Demozoo is a website dedicated to collecting and organizing the history of the demoscene, from its very early beginnnings as crack intros in the 80s, up until the current day. We are a community-driven website, where we invite everyone to contribute to the data we collect. Together, we help document the productions, people, groups and events that compose the demoscene, and everything in between.

DiscMaster: Experimental website to browse and search vintage computer files from archive.org. Thousands of new files are added daily!

DOS Games Archive: It's amazing how far computer games have progressed. But have you ever felt the urge to take a trip back in time and relive the games of the eighties and nineties? Well now you can! We have 1,231 DOS games in our archive that can be downloaded for free. You can play most DOS games in your browser as well. The games are shareware, freeware, playable demos or full versions which are released as freeware or into the public domain. All games on this website can be downloaded legally; DOS Games Archive is not a so-called abandonware website. Also, all downloads are checked for adware, malware and viruses.

Embeddable Linux Kernel Subset: This is a project to write a Linux-like OS for systems based on the Intel IA16 architecture (16 bits processors: 8088, 8086, 80188, 80186, 80286, Nec V20, V30 and compatibles).

FLEX User Group: FLEX is a superb disk-based Operating System, only 8k bytes (beat that W95, NT), open, extendable, and easily hackable! It ran on the Motorola 6800 originally, then on the fantastic 8/16-bit 6809 (as used in the CoCo and Dragon). Even though FLEX is 20 years old, I've found that there are still many FLEX systems in operation today, some even having run non-stop for over 15 years (without any software crashes…

Forth Interest Group: The Forth Interest Group (FIG) was a world-wide, non-profit organization for education in and the promotion of the Forth computer language. This website offers an on-line literature database, programming tools, reference works, public-domain and experimental implementations of the Forth programming language for various platforms, technical conferences, and connections to other Forth resources.

FreeDOS: FreeDOS is a complete, free, DOS-compatible operating system that you can use to play classic DOS games, run legacy business software, or develop embedded systems. Any program that works on MS-DOS should also run on FreeDOS.

FrogFind!: The Search Engine for Vintage Computers.

FUZIX: FuzixOS: Because Small Is Beautiful. FUZIX is a fusion of various elements from the assorted UZI forks and branches beaten together into some kind of semi-coherent platform and then extended from V7 to somewhere in the SYS3 to SYS5.x world with bits of POSIX thrown in for good measure. Various learnings and tricks from ELKS and from OMU also got blended in.

gaby.de: Gaby's Homepage for CP/M and Computer.

Giochi Abandonware (IT): Giochi Abandonware, attivo dal 2011, è il Sito Italiano interamente dedicato all'Abandonware e Retrogaming. La nostra missione è preservare i grandi Giochi del Passato (giochi vecchi PC sviluppati per MS-DOS e Windows e, in piccola parte, per sistemi Master System, Genesis).

GW-BASIC: The original source code of Microsoft GW-BASIC from 1983.

Hidden Palace: The Hidden Palace is a community dedicated to the preservation of video game development media (such as prototypes, hardware, source code, artwork, and more). This website can be utilized as a catalog for the items that we and others are able to collect and share.

Historical Source: A collection of historical source files, for education and perusal.

Ian Bell's Elite pages: “Elite” was originally written in 1984 by myself (Ian Bell) and David Braben for the BBC Microcomputer. It has since been converted to many platforms.

Legacy Update: Fix Windows Update on Windows XP, Vista, Server 2008, 2003, and 2000: This is a community-run resource to help you fix the Windows Update service on earlier versions of Windows. Since Windows XP was discontinued in 2014, followed by Windows 7 in 2020, Microsoft’s support for their earlier OSes has significantly dwindled. As XP and earlier don’t officially support modern security improvements, such as the SHA256 hash algorithm required by modern SSL and Authenticode certificates as of 2019, much of the internet has become inaccessible to these devices. Adding insult to injury, Microsoft actively removed many downloads for XP and earlier versions in 2020. In effect, working with these OSes is now incredibly difficult.

Lotus 1-2-3 for Linux: This is a native port of Lotus 1-2-3 Release 3 to Linux.

mcopyata: Copy a floppy/hard drive from one computer to another via a serial null modem connection.

mdfs.net: Software and documentation covering such subjects as Acorn BBCs, Econet and networking, SJ Research Fileservers, Z80, 6502, ARM and PDP-11 code, C programming, Co-processors and Tube systems, Harston Advanced Disk Filing System, BBC Public Domain, CP/M.

MS-DOS: The original sources of MS-DOS 1.25 and 2.0, for reference purposes.

mTCP TCP/IP applications for DOS PCs: mTCP is a set of TCP/IP applications for personal computers running PC-DOS, MS-DOS, FreeDOS, and other flavors of DOS.

Multics: Multics Source and Documentation. In order to preserve the ideas and innovations that made Multics so important in the development of computer systems, Bull HN has provided the source code for the final Multics release, MR 12.5 of November 1992 to MIT. It is a generous contribution to computer science knowledge and is provided for academic purposes. Additionally, we intend this site to become a repository for many papers and documents that were created during the Multics development as a complement to the other Multics sites.

My Abandonware: Get ready for a deep dive into PC and console retrogaming, more than 22200 games are available and waiting to be played again. Discover rare 80s games and immerse yourself into classics from the 90s and 00s. Get your dose of nostalgia and old school gaming right now! On My abandonware you can download all the old video games from 1978 to 2010 for free! You can play Pacman, Arkanoid, Tetris, Galaxian, Alter Ego, or Blackthorne, Civilization, Sim City, Prince of Persia, Xenon 2, King's quest, Ultima, Kyrandia, The Incredible Machine, Another World, Test Drive, Flashback, Lemmings!

Netatalk: Netatalk is a freely-available Open Source AFP fileserver. A UNIX, Linux or BSD system running Netatalk is capable of serving many Macintosh clients simultaneously as an AppleShare file server (AFP).

NitrOS-9: NitrOS-9 is a real-time, process-based, multitasking, multi-user, Unix-like operating system for the 6809 and 6309 processors. It runs on TRS-80 Color Computer, Radio Shack Color Computer 2, Tandy Color Computer 3 and Dragon 64. The original OS-9 was created in 1979. NitrOS-9 is the modern equivalent of that OS, and includes advanced features like support for up to 2 MB RAM and 4 GB Hard drive partitions. It is still being developed, and support is available in many mailing lists and forums.

OmniFlop: OmniFlop is a 'universal' floppy disk reader, writer, and tester for the IBM PC or compatible which can handle alien floppy disk formats not normally supported by DOS, Windows and Linux. It was first released in December 2004. OmniFlop exploits the original hardware design of the IBM PC to read, write and format disks using formats long since forgotten. You need a PC with built-in floppy drive hardware to use it. It will not work with software simulations, e.g. VMware, VirtualBox or VFD. The OmniFlop supplied here will allow you to image (read) a whole floppy disk into one file in Windows, write an image back to a floppy disk, or format a floppy disk so a disk image can be written to it. OmniFlop does not give you access to the individual files, documents, programs, robot commands or synthesizer samples (or whatever else is stored on the disk), nor will it allow you to edit files, documents, programs, robot commands or synthesizer samples.

PC/IX: Interactive UNIX, also known as PC/IX, and 386/ix were UNIX derivitives created for the IBM PC in the early 1980's. PC/IX was the first UNIX sold directly from IBM, but not the first UNIX sold for the IBM PC. (Venix/86 was the first.) The original PC/IX software sold was on 19 floppy disks and sold for 900 dollars. In 1985, 386/ix was introduced, later named Interactive UNIX.

pcmenc: Advanced PCM encoder for 8-bit sound chips.

PDP-11.RU Mirrors Archive: A large archive of various mirror sites and consolidated information on retro computers.

PPCAppStore: The PPCAppStore is a software distribution platform, for PowerPC macs, compatible with MacOS 10.4 Tiger, MacOS 10.5 Leopard and MacOS 10.6 SnowLeopard OS. It allows users to download essential applications to keep their PowerPC macs alive.

QTERM: QTERM is a CP/M terminal program which provides the following: Capture of text files - Send text files to remote - Xmodem / Modem7 / Ymodem protocol transfer - Kermit protocol transfer - VT100 emulation - Split screen mode to separate typed and received text - Script mechanism for automatic dialing and automation of other operations - Transfer of text to printer - Full user area support.

Retro Computing Internet Resources: This is a list of projects which let vintage computers connect to the internet!

RetroBridgeBBS: This software will help you transfer software to your classic Macintosh (e.g. MacOS System 6, 7, 68k Macs, etc) using the serial port. Very simply, this software runs on a modern host computer, and behaves like a BBS would back in the day. You connect your Macintosh to the host computer using serial, and then, using your vintage computer, you can search and download files from online archives (e.g. Macintosh Garden, Mac Repository). However, this “BBS” has only one user, you!

RetroBSD: RetroBSD is a port of 2.11BSD Unix intended for embedded systems with fixed memory mapping. The current target is Microchip PIC32 microcontroller with 128 kbytes of RAM and 512 kbytes of Flash. PIC32 processor has MIPS M4K architecture, executable data memory and flexible RAM partitioning between user and kernel modes.

Retrocomputing Archive: This site was created as a logical extension to the original Commercial CP/M Software Archive. The focus has been expanded to encompass all types of “classic” computer systems and their software, not just CP/M. Software and documentation for all computer systems is welcome here. Anything from the simplest 6502 based SBC to a huge VAX minicomputer; it has a home here.

romfont: VGA and BIOS rom font extraction. I have diassembled and/or searched BIOS and VGA-ROMs for fonts and extracted these. Also I have written a few tools to support this job. All extracted fonts and screenshots are available here. I have written a big table to show what is covered. Also had a look and wrote about fonts of open source BIOSes/source available.

RomWBW: RomWBW provides a complete software system for a wide variety of hobbyist Z80/Z180 CPU-based systems produced by these developer communities: RetroBrew Computers - RC2014 - retro-comp.

RSX11M.com: A site for information on the computer operating system RSX11M+ which runs on DEC PDP-11 computers.

SCO Openserver Installation ISOs: Installation ISOs for SCO Openserver are difficult to find on the internet, so I am making the ISOs I have available for download here.

Software Preservation Group: Welcome to the web site of the Computer History Museum's Software Preservation Group (formerly Software Collection Committee, or SCC)! The Software Preservation Group (SPG) of the Computer History Museum is an early exploration of how to collect software in support of the museum's overall mission. The work of the SPG includes: Preserving and collecting software; Identifying and working with other people preserving and collecting software; Sponsoring and assisting software preservation and collection activity.

Open Source freeware applications for Sun Solaris: Welcome to the No.1 archive of pre-compiled open source applications and packages for Sun Solaris, including favorites such as apache, mysql, php, gcc, Mozilla Firefox & Thunderbird.

SymbOS: SYmbiosis Multitasking Based Operating System. Preemptive multitasking - 1024 Kb dynamic memory - 2 terabyte filesystem - 100% flexible windows GUI - network capable available for your Amstrad CPC, MSX, Amstrad PCW and Enterprise 64/128.

SyncTERM: SyncTERM is a BBS terminal program which supports: Windows, Linux, OpenBSD, NetBSD, OS X, and FreeBSD.

TenFourFox: A fork of Mozilla Firefox for the Power Macintosh and Mac OS X Tiger PowerPC.

The Hello World Collection: “Hello World” is the first program one usually writes when learning a new programming language. Having first been mentioned in Brian Kernighan's tutorial to the B programming language, it became widely known through Kernighan & Ritchie's 1978 book that introduced “The C Programming Language”. Since then, Hello World has been implemented in just about every programming language on the planet. This collection includes 603 Hello World programs in as many more-or-less well known programming languages, plus 78 human languages.

The *HUMONGOUS* CP/M Software Archives: Welcome to your one-stop shop for CP/M software: the *HUMONGOUS* CP/M Software Archives, a humongous collection of the great CP/M repositories past and present. Our motto: If you can't find it here, you probably didn't look hard enough.

The Kermit Project: Kermit is the name of a file-transfer and -management protocol and a suite of computer programs for many types of computers that implements that protocol as well as other communication functions ranging from terminal emulation to automation of communications tasks through a high-level cross-platform scripting language. The software is transport-independent, operating over TCP/IP connections in traditional clear-text mode or secured by SSH, SSL/TLS, or Kerberos IV or V, as well as over serial-port connections, modems, and other communication methods (X.25, DECnet, various LAN protocols such as NETBIOS and LAT, parallel ports, etc, on particular platforms).

The KA9Q NOS TCP/IP Package: KA9Q NOS was only the second known implementation of the Internet protocols for low-end computers; the first was MIT's PC/IP, which became the basis of the now-defunct company FTP Software, Inc. Unlike PC/IP, KA9Q NOS could simultaneously act as an Internet client, a server and an IP packet router, and it could handle multiple client and server sessions at once.

The TurboDOS Museum: This website is a Work In Progress dedicated to TurboDOS; A Multiprocessor Operating System designed for multiprocessor networks of Z-80-based computers. TurboDOS is designed as a CP/M-compatible operating system. “TurboDOS was known, when CP/M ruled, as the only serious opponent to MP/M-II, the multi-user, multi-tasking version of CP/M.” - E. Roche

The Unofficial CP/M Web site: This site will be a clearing house for CP/M software. That's the good news. Now the bad news. What original source you will find on this site is all there is! The rest has been lost to the ages for one reason or another. This site is dedicated to the early days of microcomputing. Digital Research produced operating systems, utilities, and language products for early microprocessor systems. These systems included such microprocessors as the 8080, Z80, 68000, Z8001, and 8086/8088. The workhorse of the operating system for these systems was CP/M. A more advanced operating system, MP/M, allowed multi-tasking and multi-user, systems to be built.

The Walnut Creek CD-ROM Collection: Walnut Creek CDROM (of Walnut Creek, California) was an early provider of freeware, shareware and free software on CD-ROMs. The company was founded in August 1991 by Bob Bruce and was one of the first commercial distributors of free software on CD-ROMs. The company produced hundreds of titles on CD-ROMs, and ran the busiest FTP site on the Internet, ftp.cdrom.com, for many years.

VETUSWARE.COM: The biggest free abandonware downloads collection in the universe.

VOGONS Vintage Driver Library: This is a collection of drivers for vintage hardware, as collected and contributed by the upstanding members of the VOGONS Forums.

Wayzata CD-ROM Collection: Wayzata CD-ROM was one of the earliest publishers of CD-ROM software, primarily for Macintosh but also for the general ISO-9660 compatible platforms. After producing a flurry of products, the company went out of business in 1996.

WinWorld: WinWorld from the past, to the present, for the future. WinWorld is an online museum dedicated to the preservation and sharing of vintage, abandoned, and pre-release software. We offer information, media and downloads for a wide variety of computers and operating systems. Our entire library is free, open and available to everyone. Whether you're looking to go down memory lane and re-visit classic versions of Windows, do some research on computing history, or repurpose an old system that can't run the latest and greatest, we aim to be your number one source of top-quality information and downloads that other sites simply can't compare with. Get classic operating systems, applications, games and betas for every platform from PC to Mac to Amiga, right here from the software library on WinWorld.