█▓▒░C64 READY.

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.

The C64 READY. interface: the CRT display on the left showing the blue BASIC boot screen, with the side panel of controls on the right.
Theme: Classic1 / 6
The interface in the GEOS theme's dark mode: white on black.
Theme: GEOS2 / 6
The interface in the Breadbin theme's dark mode: the brown keyboard with cream text.
Theme: Breadbin3 / 6
The interface in the Phosphor theme's dark mode: amber on black.
Theme: Phosphor4 / 6
The interface in the Out Run theme's dark mode: a magenta horizon glow over violet night.
Theme: Out Run5 / 6
The interface in the Commando theme's dark mode: sand on dark brown with orange accents.
Theme: Commando6 / 6

Overview & guides

Architecture & internals