MAME

MESS shows a very MAME-like system info box on launch. (For some reason the reported resolution is one pixel off in this particular version of MESS. Oops!)

MESS (Multi Emulator Super System) is an emulator for vintage computers, gaming consoles, chess computers, and calculators. It is a descendant of the MAME arcade emulation project and just like MAME, the most important goal of MESS is highly accurate emulation, not speed. MESS and MAME are mainly preservation projects that aim to reproduce the behavior of the real hardware perfectly.

Currently, over 450 systems are supported, including the CPC and CPC Plus ranges and the GX4000.[1] This is probably the main reason for using MESS, that a single download is enough to emulate more or less every home computer and gaming console that ever existed in the late 1970s and 1980s—provided one can find a ROM set that works (see below). MESS does not have the depth of other emulators, but it sure has enormous breadth.

MESS currently does not render the border area of the CPC screen, so physical screen resolution in MESS is 640x200 as the system info box shows. (This is not the same for all systems, e.g. on an emulated C64, the borders are there.)

MESS runs on Windows, Mac OS X, Linux, and FreeBSD.

Sources: [2] and [3]

Supported file types can also be shown with the "-listmedia" command line option.

MESS generally supports two keyboard mode command line options: emulated (the default; based on key position) and natural (command line option "-natural"; based on the character generated by a key, e.g. pressing "z" will always generate a "z" on the emulated system, even if the keyboard positions are different). In emulated mode, keys can also be remapped in the menu: press Tab, then select Input (this system).

Just as in MAME, some MESS ROMs have parent ROMs that also need to be installed. E.g., cpc6128.zip also requires cpc464.zip to run.

ROMs often only work with a specific version of MESS. This does not seem to affect CPC ROMs, but other systems sometimes give an error message when ROM filenames or checksums do not match what MESS expected.

Various GUI front-ends for MESS exist for Windows, Linux, and OS X—see the list here: [4]

MessMenu on OS X with a CPC ROM selected. Currently, seven different CPC models are supported, including some regional variants (French and Swedish).

• MAME at the English-language Wikipedia
• Official site
• MESS user's manual
• CPC ROMs for MESS (look for cpc*.zip)