Multi Emulator Super System (MESS) is an

emulator In computing, an emulator is hardware or software that enables one computer system (called the ''host'') to behave like another computer system (called the ''guest''). An emulator typically enables the host system to run software or use pe ...

for various consoles and computer systems, based on the

MAME MAME (formerly an acronym of Multiple Arcade Machine Emulator) is a free and open-source emulator designed to recreate the hardware of arcade game systems in software on modern personal computers and other platforms. Its intention is to preserve ...

core. It used to be a standalone program (which has since been discontinued), but is now integrated into MAME (which is actively developed). MESS emulates

portable Portable may refer to: General * Portable building, a manufactured structure that is built off site and moved in upon completion of site and utility work * Portable classroom, a temporary building installed on the grounds of a school to provide ...

and console gaming systems, computer platforms, and

calculators An electronic calculator is typically a portable electronic device used to perform calculations, ranging from basic arithmetic to complex mathematics. The first solid-state electronic calculator was created in the early 1960s. Pocket-size ...

. The project strives for accuracy and portability and therefore is not always the fastest emulator for any one particular system. Its accuracy makes it also useful for homebrew game development. As of April 2015 MESS supported 994 unique systems with 2,106 total system variations. However, not all of the systems in MESS are functional; some are marked as non-working or are in development. MESS was first released in 1998 and has been under constant development since. MAME and MESS were once separate applications, but were later developed and released together from a single source repository. MAMEDEV member David Haywood maintained and distributed UME (Universal Machine Emulator) which combined much of the functionality of MAME and MESS in a single application. On May 27, 2015, MESS was formally integrated with MAME and became a part of MAME.

License

MESS was distributed under the MAME Licence, which allowed for the redistribution of

binary file A binary file is a computer file that is not a text file. The term "binary file" is often used as a term meaning "non-text file". Many binary file formats contain parts that can be interpreted as text; for example, some computer document fil ...

s and

source code In computing, source code, or simply code, is any collection of code, with or without comments, written using a human-readable programming language, usually as plain text. The source code of a program is specially designed to facilitate the ...

, either modified or unmodified, but disallowed selling MESS or using it commercially. The license is similar to other

copyleft Copyleft is the legal technique of granting certain freedoms over copies of copyrighted works with the requirement that the same rights be preserved in derivative works. In this sense, ''freedoms'' refers to the use of the work for any purpose ...

licenses in requiring that rights and obligations provided in the license must be remain intact when MESS or derivative works are distributed. In addition to the MESS Licence, The MESS Team required that: "MESS must be distributed only in the original archives. You are not allowed to distribute a modified version, nor to remove and/or add files to the archive. Adding one text file to advertise your web site is tolerated only if your site contributes original material to the emulation scene." The MAME license required source code be included with versions of MESS that are modified from the original source, while the MESS legal page states that when distributing binary files "you should also distribute the source code. If you can't do that, you must provide a pointer to a place where the source can be obtained." While MESS was available in both binary and source code forms, the restrictions on commercial exploitation cause it to fall outside of the Free Software Foundation's definition of

free software Free software or libre software is computer software distributed under terms that allow users to run the software for any purpose as well as to study, change, and distribute it and any adapted versions. Free software is a matter of liberty, n ...

. Similarly MESS was not considered to be

open source software Open-source software (OSS) is computer software that is released under a license in which the copyright holder grants users the rights to use, study, change, and distribute the software and its source code to anyone and for any purpose. Open ...

if appraised according to the criteria of the Open Source Definition.

Challenges

Generally the emulation only includes raw

hardware logic Electronic hardware consists of interconnected electronic components which perform analog or logic operations on received and locally stored information to produce as output or store resulting new information or to provide control for output act ...

, such as for the

CPU A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, a ...

and

RAM Ram, ram, or RAM may refer to: Animals * A male sheep * Ram cichlid, a freshwater tropical fish People * Ram (given name) * Ram (surname) * Ram (director) (Ramsubramaniam), an Indian Tamil film director * RAM (musician) (born 1974), Dutch * ...

, and specialized DSPs such as tone generators or video sprites. The MESS emulator does not include any programming code stored in ROM chips from the emulated computer, since this may be copyrighted software. Obtaining the ROM data by oneself directly from the hardware being emulated can be extremely difficult, technical, expensive, and even destructive since it may require decapping or desoldering of

integrated circuit An integrated circuit or monolithic integrated circuit (also referred to as an IC, a chip, or a microchip) is a set of electronic circuits on one small flat piece (or "chip") of semiconductor material, usually silicon. Large numbers of tiny ...

chips from the circuit board of the device they own. A desoldered IC is placed into a chip reader device connected to a USB or

serial port In computing, a serial port is a serial communication interface through which information transfers in or out sequentially one bit at a time. This is in contrast to a parallel port, which communicates multiple bits simultaneously in parallel. ...

of another computer, with pin sockets on the reader specifically designed to match the chip package shape in question, to perform a memory dump of the ROM to a data file. Removal of a soldered chip is often far easier than reinstalling it, especially for extremely small surface mount technology chips, and the emulated device in question may be effectively destroyed beyond recovery after the ROM has been removed for reading. However, if one has a working system, it may be far easier to dump the ROM data to tape, disk, etc. and transfer the data file to one's target machine.

Uses

In 2013 the

Internet Archive The Internet Archive is an American digital library with the stated mission of "universal access to all knowledge". It provides free public access to collections of digitized materials, including websites, software applications/games, music, ...

began to provide

abandonware Abandonware is a product, typically software, ignored by its owner and manufacturer, and for which no official support is available. Within an intellectual rights contextual background, abandonware is a software (or hardware) sub-case of the ...

games browser-playable via ''JSMESS'' (a

JavaScript JavaScript (), often abbreviated as JS, is a programming language that is one of the core technologies of the World Wide Web, alongside HTML and CSS. As of 2022, 98% of websites use JavaScript on the client side for webpage behavior, of ...

port of the MESS emulator), for instance, the

Atari 2600 The Atari 2600, initially branded as the Atari Video Computer System (Atari VCS) from its release until November 1982, is a home video game console developed and produced by Atari, Inc. Released in September 1977, it popularized microprocesso ...

game ''

E.T. the Extra-Terrestrial ''E.T. the Extra-Terrestrial'' (or simply ''E.T.'') is a 1982 American science fiction film produced and directed by Steven Spielberg and written by Melissa Mathison. It tells the story of Elliott, a boy who befriends an extraterrestrial, d ...

''.

References

External links

*
MESS User Manual

JSMESS

Historical Software
at

Arcade Database
Database containing details of any game supported by Mame/Mess, including past versions. There are images, videos, programs for downloading extra files, advanced searches, graphics and many other resources. {{Portal bar, Video games Classic Mac OS emulation software Linux emulation software Macintosh platform emulators MacOS emulation software Multi-emulators Nintendo Entertainment System emulators PlayStation emulators Video game emulation Windows emulation software X86 emulators Free video game console emulators

License

Challenges

Uses

See also

References

External links