View source for Multi Emulator Super System

{{short description|Multi-system emulator}}
{{redir|MESS||Mess (disambiguation)}}
{{Infobox software
| name = MESS
| title = 
| logo = MESS-Logo.png<!-- Image name is enough -->
| logo caption = 
| logo size = 180px
| logo alt = MESS icon
| screenshot = <!-- Image name is enough -->
| caption = 
| screenshot size = 
| screenshot alt = 
| developer = Originally MESS [[Virtual team|Team]], now MAME Team
| released = {{Start date and age|1998}}
| discontinued = yes
| latest release version = 0.161
| latest release date = {{Start date and age|2015|04|29|df=yes}}
| latest_preview_version = 
| latest_preview_date = 
| operating_system = [[Cross-platform]]
| platform = 
| genre = [[Emulator]]
| license = Since 2016: [[GNU General Public License|GPL-2.0-or-later]]<ref>{{Cite web|url=http://mess.redump.net/license|title=MESS License [MESS]|website=mess.redump.net |date=14 May 2025 }}</ref><br />Until 2016: Custom<ref>{{cite web|url=http://www.mess.org/license|title=MESS License: Custom|archive-url=https://web.archive.org/web/20160324182136/http://www.mess.org/license|archive-date=2016-03-24}}</ref>
| website = {{plainlist|
* {{url|www.mamedev.org}}
* {{webarchive |url=https://web.archive.org/web/20250514072652/http://mess.redump.net/|title=mess.redump.net|date=May 14, 2025}}
}}
}}

'''Multi Emulator Super System''' ('''MESS''') was an [[emulator]] for various [[video game consoles|consoles]] and computer systems, based on the [[MAME]] core. It used to be a standalone program (which has since been discontinued), but is now integrated into MAME (which is actively developed).
MESS emulated [[Portable computer|portable]] and [[Video game consoles|console gaming systems]], [[Personal computers|computer platforms]], and [[calculators]]. The project strived for accuracy and portability and therefore was not always the fastest emulator for any one particular system. Its accuracy made it also useful for [[homebrew (video games)|homebrew]] game development.<ref>{{cite book | title = Game Console Hacking: Xbox, Playstation, Nintendo, Atari, & Gamepark 32 | last = Grand | first = Joe |author2=Frank Thornton |author3=Albert Yarusso | isbn = 1-931836-31-0 | publisher = Syngress | year = 2004 | page = 506 }}</ref>

As of April 2015 MESS supported 994 unique systems with 2,106 total system variations.<ref>{{Cite web |title=Welcome to the MESS Wiki! [MESS] |url=http://mess.redump.net/ |archive-url=https://web.archive.org/web/20250514072652/http://mess.redump.net/ |archive-date=May 14, 2025 |website=mess.redump.net}}</ref> MESS was first released in 1998 and was under development up until 2015.

MAME and MESS were once separate applications, but were later developed and released together from a single source repository.<ref>{{cite web|title=Let the games begin|url=http://mamedev.org/?p=373|publisher=MAME development team|access-date=26 December 2012}}</ref> 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.<ref>{{cite web |url= http://mamedev.emulab.it/haze/2013/01/11/ume-0-148/ |title= UME 0.148 (Universal Machine Emulator) |publisher= David Haywood |access-date= 11 January 2013}}</ref> On May 27, 2015, MESS was formally integrated with MAME and became a part of MAME.<ref>{{Cite web|url=https://www.mamedev.org/?p=406|title=MAMEdev.org &#124; Home of The MAME Project|website=www.mamedev.org}}</ref>

== License ==
{{see also|MAME#License}}

MESS was distributed under the [[MAME#License|MAME Licence]], which allowed for the redistribution of [[binary file]]s and [[source code]], either modified or unmodified, but disallowed selling MESS or using it commercially.<ref>{{cite web |url= http://www.mess.org/license |title= MESS Licence |publisher= The MESS Development Team |access-date= 24 March 2016 |url-status= bot: unknown |archive-url= https://web.archive.org/web/20160324182136/http://www.mess.org/license |archive-date= 24 March 2016 }}</ref> The license is similar to other [[copyleft]] 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."<ref>{{cite web |url= http://www.mess.org/legal.php |title= MESS Legal |publisher= The MESS Development Team |access-date= 4 July 2010 |url-status= bot: unknown |archive-url= https://web.archive.org/web/20100704041046/http://www.mess.org/legal.php |archive-date= 4 July 2010 }}</ref> 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|Free Software Foundation's]] definition of [[free software]]. Similarly MESS was not considered to be [[open source software]] if appraised according to the criteria of the [[Open Source Definition]].

== Challenges ==
{{main|ROM image}}

Generally the emulation only includes raw [[hardware logic]], such as for the [[CPU]] and [[RAM]], and specialized [[digital signal processor|DSP]]s such as tone generators or video [[Sprite (computer graphics)|sprites]]. The MESS emulator does not include any programming code stored in [[read only memory|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]] 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]] 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 will be 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]] began to provide select games [[Web browser|browser]]-playable via ''JSMESS'' (a [[JavaScript]] port of the MESS emulator), for instance, the [[Atari 2600]] game ''[[E.T. the Extra-Terrestrial (video game)|E.T. the Extra-Terrestrial]]''.<ref>{{cite web|url=https://www.theverge.com/2013/10/25/5028974/internet-archives-new-historic-software-collection|title=The Internet Archive puts Atari games and obsolete software directly in your browser|first=Adi |last=Robertson|date=2013-10-25| access-date=2013-10-29 |publisher=[[The Verge]]}}</ref>

== See also ==
* [[List of computer system emulators]]
* [[List of video game emulators]]

== References ==
{{Reflist|30em}}

== External links ==
* {{Official website|http://mess.redump.net/}}
* [https://web.archive.org/web/20250514085429/http://mess.redump.net/mess/howto MESS User Manual]
* [http://www.archiveteam.org/index.php?title=Javascript_Mess JSMESS]
* [https://archive.org/details/historicalsoftware Historical Software] at [[Internet Archive]]
* [http://adb.arcadeitalia.net 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.

{{Nintendo emulators}}
{{Sony emulators}}
{{Portal bar|Video games}}

[[Category:1998 software]]
[[Category:Classic Mac OS emulation software]]
[[Category:Linux emulation software]]
[[Category:Macintosh platform emulators]]
[[Category:MacOS emulation software]]
[[Category:Multi-emulators]]
[[Category:Nintendo Entertainment System emulators]]
[[Category:PlayStation emulators]]
[[Category:Video game emulation]]
[[Category:Windows emulation software]]
[[Category:X86 emulators]]
[[Category:Free video game console emulators]]