Documentation
A cycle-exact Commodore 64 that runs entirely in your browser — guides for using it, and deep-dives on how it is built, chip by chip.
The emulator brings the whole breadbin to life: the 6510 CPU with every illegal opcode, VIC-II graphics down to the raster line, both SID sound chips (6581 & 8580), the CIA timers, PLA memory banking, and a true 1541 disk drive that handles the nastiest custom fastloaders.
Every chip is held as close as possible to the real hardware, checked against hundreds of cycle-exact test programs alongside a growing unit-test suite of 2,600+ labeled tests.
Below, Overview & guides is for using the emulator; Architecture & internals goes inside it, chip by chip.
Theme: Phosphor1 / 8
Theme: Classic2 / 8
Theme: GEOS3 / 8
Theme: Breadbin4 / 8
Theme: Out Run5 / 8
Theme: Commando6 / 8
Theme: Art Deco7 / 8
Theme: Lookout Point8 / 8
Overview & guides
- Getting Startedfrom blank screen to a running demo
- What's Newchanges in each release
- User Guideevery panel, dialog and button
- Feature listeverything it supports
- Known Issueswhat is missing or rough
- Aboutwhat it is and who made it
- Specifications & creditsreferences, formats and thanks
- Tape restorationbringing worn cassettes back
- Build Device pluginswrite for User Port and IEC
- Inside the C64the chips, connections and devices behind the machine
- C64 READY. and VICEhow the two compare
Architecture & internals
- Architecture overviewthe whole emulator on one page
- Component statushow close each part is to the hardware
- Machinewiring, cycle order, interrupts
- 6510 CPUmicroops, addressing, illegal opcodes
- VIC-IItiming, bad lines, sprites, rendering
- SIDvoices, filter, audio worklet
- Memorybanking, I/O routing, cartridges
- 1541 disk driveGCR, IEC bus, true drive emulation
- Datasettetape deck, TAP and WAV
- Retro Vibesthe 3D viewer
- Performancekeeping a cycle-accurate C64 fast
- Test suitetests, tools and VICE cross-checks