Photograph of Commodore 64 / 64C
Evan-Amos / Wikimedia Commons / Public domain

Best-selling home computer. Cartridge, IEC, SID, and video replacements are a mature open-hardware scene.

Also known as: C64, C64C, SX-64

Published open-source PCB projects

Other catalogued projects

Mod License Notes
Kung Fu Flash Open source (GPL-3.0-or-later) Open STM32 cartridge that loads CRT/PRG/SID files from SD and replaces many classic carts.
1541 Ultimate II+ Mixed / partial source IEC/cartridge emulator. VHDL and tools have public trees; assembled units are commercial.
Ultimate 64 Mixed / partial source FPGA C64 motherboard sold as a drop-in. Gateware licensing is mixed.
EasyFlash 3 Open source (GPL-3.0-or-later) Open-ish flash cartridge platform used by many CRT releases.
OpenC64Cart Open source Open KiCad cartridge PCB for Commodore 64 homebrew and flash carts. Drop-in C64 expansion-port board.
C64 flash cartridge Open source (CERN-OHL-1.2) Open rewritable Commodore 64 game cartridge compatible with the Universal Mega Dumper.
SIDKick Open source Open-source drop-in MOS 6581/8580 SID replacement. FPGA/MCU based; plays SID tunes on original C64 hardware.
SIDKick-pico Open source Open RP2040 SID replacement by the SIDKick author. Smaller, cheaper successor to the original SIDKick.
Tapuino Open source Open Arduino-based C64 tape emulator. Loads TAP files from SD in place of a Datasette.
Turbo Chameleon 64 Proprietary Commercial FPGA cartridge with C64/C64DTV extras.

Browse these projects in the 3D PCB mod directory. Open-source rows can be shallow-cloned into the git bucket. Generated board renders belong on the artifact CDN, not in git. See the catalog wiki note.