Clock Signal ('CLK') is an emulator for tourists that seeks to be invisible. Users directly launch classic software, avoiding the learning curves associated with emulators and with classic machines.

macOS and source releases are hosted on GitHub. For desktop Linux it is also available as a Snap.

This emulator seeks to offer:

single-click load of any piece of source media for any supported platform;
with a heavy signal processing tilt for accurate reproduction of original outputs;
while minimising latency.

It currently contains emulations of the:

Acorn Electron;
Amstrad CPC;
Apple II/II+ and IIe;
Atari 2600;
Atari ST;
ColecoVision;
Commodore Vic-20 (and Commodore 1540/1);
Enterprise 64/128;
Macintosh 512ke and Plus;
MSX 1 and 2;
Oric 1/Atmos;
Sega Master System;
Sinclair ZX80/81; and
Sinclair ZX Spectrum.

Commodore Amiga emulation is also present, but for now remains wilfully inaccurate.

On the Mac it is a native Cocoa and Metal application; under Linux, BSD and other UNIXes and UNIX-alikes it uses OpenGL and can be built either with Qt or with SDL.

This release:

continues improvements to the MSX 2, especially its video chip and this emulator's automated detection of cartridge types;
corrects the 65c02's BCD results, where they differ from a vanilla 6502;
corrects the 65816's state after a BRK while in emulation mode; and
resolves some timing discrepancies in some of the unofficial NOPs on the base 6502.