Homebuilt 6502 Computers & Hardware

• Adam's Great 6502 Projects - Adam Luoranen presents some good beginning 6502 tips and projects, including a simple LED-blinker project and details for interfacing a KS0108-based graphical LCD panel.
• Alexis' ROMless 6502 Microcomputer - Alexis Kotlowy-Brown has created a 6502-based single board computer programmable only by DIP switches in the spirit of computers like the Altair 8800.
• André's Gecko and CS/A65 - André Fachat has written his own operating system for several 6502-based homebuilt computers which even includes an experimental TCP/IP protocol stack and SCSI interface. Andre also has his own cross-assembler, file format, and standard library.
• BigDumbDinosaur's Proof of Concept - BDD has built a "Proof of Concept" single board computer around the 65C816. It includes 128KB static RAM, NXP 2692A DUART, Maxim DS1511Y RTC, and more. Detailed design descriptions, memory map, schematics, and PCB layout files are all provided.
• Buri: A Homebrew 6502 Microcomputer - Rich Wareham has built a simple 65C02-based computer that can drive a VGA monitor. Schematics, PCB layouts, source code, and an emulator are all provided. Rich also has a series of YouTube videos about the project.
• Breadboard a Computer - J.B. Calvert's page is a tutorial that uses small 6504-based circuits to teach the fundamentals of a microcomputer system.
• Brian's S/O/S SyMON II - Brian M. Phelps created S/O/S SyMON II, a 65(C)02 BIOS with a monitor and assembler. His pages contain photos and descriptions of several 6502 SBC projects along with documentation and software for S/O/S SyMon II.
• Chris Cowen's Jimini Platform - CPC Microsystems is a website created by Christopher Cowen detailing some of his microcomputer projects. One of his systems, the Jimini Platform, is a modular 6502-based system which uses a backplane similar to VME and is programmable in C using CC65.
• Chris Ward's 6502 Project - Similar to DIY6502, Chris Ward's board has 32K SRAM, 8K EEPROM, two 6522 VIAs, and one 6551 ACIA. Chris also has a schematic for his parallel port EEPROM programmer circuit. ( Archived version is better formatted.)
• Daryl's 65C02 SBC - Daryl Rictor has managed to squeeze a 65C02, 6526, RAM, ROM, and all associated circuitry on a tiny 3.8"x2.5" board. His page includes schematics, monitor software, and an interesting 65C02 simulator for Windows.
• Dieter's M02 - Dieter Müller has built a homebuilt 6502-based project without a microprocessor IC or even FPGAs. Instead, he built his own 6502 work-alike using 40 ICs on two PCBs: mostly spare EPROMs and 74xx-series logic. The custom CPU has several improvements over the original 6502, such as a 16MB address range, most 65C02 opcodes, and some 65C816 features. The M02 computer includes a graphical LCD display and keyboard, and runs the KERNAL and BASIC ROMs from the Commodore 64.
• Dieter's DRC2 - Based in part on Daryl Rictor's SBC-2 design, Dieter Müller's DRC2 computer supports a graphics LCD display and PS/2 keyboard. His page includes technical details, photos, and schematics.
• Dirk's 6502 Home Computer - Dirk Grappendorf has built a mobile home computer in a 3-D printed case, all hardware and software open-sourced. Written up as a development blog, but see also the git repository.
• Dolo Miah's 6502 Homebrew Computer - Dolo Miah's homebrew machine is housed in a BBC Micro case, but it's an original design, with video, sound, a bespoke monitor, and solid state storage. It uses a 128k SRAM but does not yet have a banking system. This project is working but still being expanded.
• Douglas' DIY-6502 - Douglas Beattie has constructed his own "do-it-yourself" 6502 computer that include 2K or 8K ROM, 2K RAM, a 6551 ACIA for RS-232 and a 6522 VIA for I/O functions. This page also featues his own macro cross assembler.
• Erik's DCF Decoder - Erik Van den Broeck has built a small 6502 board to decode and display a signal from a DCF receiver, it includes a programmable clock with four independent outputs.
• Eudaemons' Shoe Computers - Currently the only "evil" 6502 project on the web, this page describes how the Eudaemons used a 6502 board hidden in the sole of a shoe to cheat at the roulette table.
• Garth Wilson's Projects - Garth Wilson has built many 6502 projects over the years and has documented several of them on 6502.org, complete with photos and schematics. For more on the workbench computer, see http://wilsonminesco.com/BenchCPU/.
• Georg's OSIRISflash - This German-only page describes Georg Lachenmeier's alternative energy controller, which is based on the Mitsubishi 50747, a 6502 instruction set compatible processor.
• Grant's MicroUK101 - Grant Searle has created his own computer based on the Compukit UK101 that communicates via a serial port and includes a monitor program and version of Microsoft BASIC. Everything you need to build it yourself can be found on his web page.
• Heiko's MARVIN-1 - German language pages describing Heiko Pruessing's homebuilt computer, MARVIN-1. This computer is built on a large breadboard. The hardware includes a serial port implemented with an Arduino, an SD card interface, and 6581 SID sound. The firmware includes ports of Steve Wozniak's Apple monitor and Lee Davison's EhBASIC interpreter.
• John's Hardware Projects - John Kortink built several 6502-related projects, including a remake of the Acorn 6502 Second Processor with contemporary parts.
• Rob's Electronics Projects - Rob Greene has been working on a 65C02-based computer that uses a PIC microcontroller subsystem to provide a VGA graphics display.
• Jeff's KimKlone - Jeff Laughton created the KimKlone, a computer that uses a standard 65C02 enhanced by off-chip circuitry. Its features include extensions that give it a 16MB address space and hardware acceleration for the Forth programming language.
• Jonathan Foucher's PLANCK 65c02 is an open-hardware, extensible 65c02-based computer, inspired by the RC2014 modular computer but with SBC capabilities and a different bus design
• Joachim's 65816 Projects - Joachim Deboy designed and built two 65816-based computers. His second computer, PC65816 V2, includes a CRT controller, ethernet, IDE interface, and a real time clock. These pages detail his projects with schematics, photos, CPLD files, software, and more.
• Klaus' 6502 Board - Klaus Mussler designed and built a small printed circuit board with 32K of RAM, 16K of ROM, three VIAs for I/O, and a 6551 ACIA and MAX232 circuit for RS-232 communications.
• Krzysztof's Projects - Krzysztof Swiecicki is a 6502 enthusiast from Poland. He has built some very interesting projects, including a 16450-based COM port, AD1848-based audio output, an SBC with an overclocked 65C02, and a fuel injection computer based on the 65SC816.
• LC64 - a modular PLCC 6502 computer - Blog describing a C64-like computer with a TFT display and a modular 65C02-based computer built with multiple cards.
• Lee's 6502-Based Projects - A pen plotter, complete 6502-based single board computer, I2C and IDE interfaces, the EhBASIC interpreter, and more can all be found on Lee Davison's project page.
• MB01 - 65C816/65C02 Computer - Marco Granati's MB01 "small system", with a mainboard and 9 Eurocard slots. The mainboard contains simple peripherals and decode, the CPU (either 65C02 or 65C816) is on one of the Eurocards. RAM and ROM are on other cards, as are a floppy controller and a serial controller
• MKHBC-8-R1 - Marek Karcz presents his breadboarded prototype single board computer.
• Mike Genovy's 6502 Stuff - Documents the construction of a 6502-based SBC and its implementation in a homebrew security system; including schematics, source code, and several photographs.
• Mike Naberezny's 6504 SBC - A simple single board computer based on the 6504. It uses half of a 2764 for ROM (4K) and a 6532 RIOT for I/O. This page includes the schematic, source code, and photographs.
• Pete's Robot - "U2PO" is an autonomous 6502-based robot built by Pete McCollum. Pete's website includes also includes other projects and robots like VICBOT which is based on a Commodore VIC-20.
• Phil's 'The Great 6502 Computer Project' - Phil Pemberton's 6502-based computer is based on a backplane design. This site includes schematics for the CPU and UART cards.
• Veronica - Quinn Dunki blogs the development of her 6502-based system, including etching the PCBs.
• Rich's My6502 - Richard Cini's website has information on classic computers and his own self-designed 6502 computer called My6502.
• Rich12345's Hardware Page - Interesting 6502-related hardware projects and documents, including "Wozbot", an Apple II-based robot.
• Roland's Atom-in-PC - Roland Leurs has built an entire 6502-based Atom computer on a PC ISA expansion card that even runs BBC BASIC. The 6502 communicates with the PC via an 8255 PPI.
• RW6HRM 6502 SBC Project - Andy Vorontsov has a Russian language site describing his 6502 SBC with 47K RAM, 16K ROM, an 8255 PPI, and an 8253 PIT. It runs OSI BASIC using a serial terminal for its console. Schematics and photos are included.
• Ryan's Nixie Clock - Ryan Brooks built a Nixie tube clock that is driven by a 6502 with 8K RAM, 8K EPROM, and a 6522 VIA. The RAM used is a Dallas DS1742, which also acts as the real time clock. His page includes photos, schematics, and source code.
• Samuel's Kestrel Project - Samuel Falvo has built a small number of 65C816-based projects. His site contains schematics, software, and design documents. ( Archive of previous site.)
• Steckschwein - German language pages detailing a 65C02 computer built on a breadboard, including 16550 UART, TMS9929 Video Display Processor, 64K static RAM, 8K ROM, and 65C22 VIA. The software includes bit-banged SPI for the 65C22 and various SPI peripherals are attached such as an RTC and SD card. The site contains schematics, source code, and a blog.
• Meadow 6502 SBC - Scott Chidester presents the design and source files for his single board computer, including the ~8k Meadow Operating System.
• Seth's 6502 Homebrew Computer - Seth Morabito built his SBC using a Rockwell R65C02, 6522 VIA, 6551 ACIA, 32KB of EPROM, and 32KB of SRAM. It uses a serial terminal for its console and runs EhBASIC. The page includes schematics and photos.
• Simon's Beer Brewing Bender - Simon Jansen has built a replica of Bender, a robot character from the television series Futurama. In addition to brewing beer, Simon's project includes a 6502 SBC with IR control and audio playback.
• Sprow's MiniB - This homebuilt computer is based on the BBC Micro. Smaller than a 3.5" floppy disk, its features include a 20x4 LCD display, 128K Flash ROM, a Real Time Clock, and a programmable logic device.

  6502 CPU Projects in HDL (for FPGA)

• André Fachat's 65k architecturally extended core (VHDL)
• Andrew Holme's phase-accurate core built from the visual6502 transistor-level netlist (Verilog)
• Arlet Ottens' 6502 Core (Verilog)
• Daniel's T65 - Daniel Wallner has created T65, a free 6502 VHDL core that supports the 6502, 65C02, and 65C816 instruction sets. A reference SoC design is also provided, complete with ROM, RAM, and two 16450-compatible UARTs. (There is at least one bug here, with the B bit: see also the PACEDev version which is the latest, and the fpgaarcade version)
• Free-6502 - David Kessner's claim was to have written the world's first free VHDL 6502 core. The original site at http://www.free-ip.com/ is dead, so we link to the Wayback Machine at the Internet Archive. However, Robert Sprowson's version found here might be preferred, as it has BCD support.
• Dennis Kuschel's MyCpu Compact core (VHDL)
• Ian Chapman's lattice6502 core (VHDL)
• Jens Gutschmidt's Rockwell R6502 true cycle Core - by (VHDL)
• Jens Gutschmidt's Rockwell R65C02 true cycle Core - by Jens Gutschmidt (VHDL)
• Michael A Morris' 65C02 core (Verilog and microcode)
• MicroCore Labs' MCL65 cycle-accurate 6502 core.
• Dr Naohiko Shimizu's 6502 core (SFL translates to Verilog)
• Oleg Odintsovs' phase-accurate core (Verilog)
• Paul Gardner-Stephen's GS4502B (VHDL) (see also this blog post and forum thread)
• Peter Wendrich's cycle exact 6502/6510 Core (VHDL) (see also Alan Daly's improved R65C02 version.)
• Retromaster's A2601 System (VHDL)
• Rob Finch's 6502 Core (Verilog)
• Ruud Baltissen's rb65-10d Core (VHDL)
• Sprow's 6502 Core (based on Free-6502) (VHDL)
• Thomas Skibo's 6502 core in his PET project (Verilog)
• PSALM - Tim Köhler's German-only page describing a project that reverse-engineered the 6502 to produce a VHDL core of an asynchronous (clockless) 6502.

  Homebuilt 6502 Software Projects

• Adam's uIP - Adam Dunkels has written a free, small TCP/IP stack in C which has been ported to x86, 8051, and 6502 systems.
• Andre's GeckOS/A65 - Andre Fachat has written a small 6502 multitasking operating system that runs on the Commodore 64 and PET computers as well as his homebuilt 6502 projects.
• David's Acheron VM - David Holz has written a reconfigurable 16-bit virtual CPU for 6502 systems.
• David's CP/M-65 - David Given started his CP/M-derived operating system in 2022 and has released it under a two-clause BSD license. Unlike CP/M itself, David's system supports relocatable binaries to enable machines with incompatible memory maps to run the same programs. Ports of the system are available for several computers. The system is developed using tools on a modern computer, with the core components (BIOS, BDOS, and CCP) being written in assembly and the utility programs being written in C.
• Dietrich's CPM-65 - Dietrich Lausberg worked on his CP/M-derived operating system throughout the 1990's and was still improving it in 2022, when he released it as open source under a GPL 3.0 license. It runs on his expanded Elektor Junior computer but can be adapted for other machines. The system is written entirely in assembly language and can assemble itself. It is a very complete system with full source code available for the OS, its assembler, languages (BASIC and FORTH), and many utility programs.
• Richard's DOS/65 - Richard Leary has written DOS/65, an interesting operating system with file system compatibility to CP/M-80 (and other similarities).
• Lee's EhBASIC - EhBASIC, or Enhanced 6502 BASIC, is a very advanced and easily portable BASIC interpreter for 6502-based systems from Lee Davison.

• See also the Source Code Repository for more 6502 software in assembly language.

  Reverse Engineering Projects

• Visual Transistor-level Simulation of the 6502 CPU - This incredible browser-based simulator in JavaScript was made by photographing a 6502 chip die, converting those images to vector polygons, then building maps of transistor connections from those. It is an accurate representation of the 6502 in its most intricate details.