Master System emulators

Sega Master System

Top: Sega Master System. Bottom: Sega Game Gear.
Developer	Sega
Type	Home video game console
Generation	Third generation
Release date	1985
Discontinued	1996
Predecessor	SG-1000
Successor	Genesis / Mega Drive
Emulated	✓

The Sega Master System (SMS) is an 8-bit console released by Sega on October 20, 1985, in Japan (as "Mark III". In all actuality, the Master System and Mark III differ a bit due to the original Japanese release having more features, such as card functionality and backward compatibility with SG-1000, which the Master System lacks) and in September of 1986 in the US. It was retailed for $199.99. It had a Zilog Z80A at 4 MHz with 8 KBs of RAM and 16 KBs of VRAM. It had a Yamaha YM2602B VDP GPU. It was designed to be a direct competitor to the Nintendo Entertainment System and was technically superior to it in some ways. The Sega Game Gear was released in April of 1991 and was a competitor for the Game Boy. It had a backlit screen, color, and a nice-looking design. It retailed for $149.99. It had a Zilog Z80 CPU at 3.5 MHz with 8 KBs of RAM and 16 KBs of VRAM.

There are a lot of hardware similarities between the SMS and the Game Gear (GG). Notably, SMS game cartridges can actually be played on the Game Gear via an adapter. For this reason, most SMS emulators can also run GG games.

Internally the Master System extends Sega's older SG-1000 by adding more RAM and a single new video mode; since the SG-1000 was built from the same CPU, video, and audio chips as the ColecoVision. Many Master System emulators also run ColecoVision games.

Emulators

Name	Platform(s)	Latest Version	System E	Game Gear	libretro	Retro Achievements	Sprite Replacement	Accuracy	Netplay	FLOSS	Active	Recommended
PC / x86
Genesis Plus GX*		libretro core	✗	✓	✓	✓	✗	Very high	✓	NC	✓	✓
MAME		0.259 libretro core	✓	✓	✓	✗	✗	?*	✗	✓	✓	✓
ares		v133	✗	✓	✗	✗	✗	High	✗	✓	✓	✓
Emulicious		2023-09-30	✗	✓	✗	✗	✗	Very high	✗	✗	✓	✓
BizHawk		Dev builds 2.9.1	✓	✓	✗	✓	✗	Very high	✗	✓	✓	~
Cega		git	✗	✓	✗	✗	✗	Cycle	✗	✓	✓	TBD
FinalBurn Neo		libretro core Stable WIP builds	✓	✓	✓	✓	✗	?	?	NC	✓	TBD
Snepulator		git	✗	✓	✗	✗	✗		✗	✓	✓	TBD
Mednafen		1.31.0-UNSTABLE	✗	✓	✗	✗	✗	?	✓	✓	✓	✗
Phoenix		2.8.JAG	✗	✓	✗	✗	✗	Very high	✗	✗	✗	✗
higan		v110	✗	✓	✓	✗	✗	High	✗	✓	✗	✗
TwoMbit		1.0.5	✗	✓	✗	✗	✗	Very high	✗	✓	✗	✗
CLK		2023-09-10	✗	✗	✗	✗	✗	Very high	✗	✓	✓	✗
Gearsystem		3.4.1	✗	✓	✓	✓	✗	High	✗	✓	✓	✗
MasterGear		4.9.3	✗	✓	✗	✗	✗	High	✗	✗	✓	✗
Pantheon		13.018	✗	✓	✗	✗	✗	High	✗	✗	✓	✗
Kega Fusion		3.64	✗	✓	✗	✗	✗	Mid	✓	✗	✗	✗
PicoDrive		libretro core 1.93	✗	✗	✓	✓	✗	Mid	✓	NC	✓	✗
FreezeSMS		4.6	✗	✓	✗	✗	✗	Very high	✗	✗	✗	✗
DarcNES		9b0401/9b0313	✗	✓	✗	✗	✗	Low	✗	✓	✗	✗
MEKA		0.8-alpha (2023-08-26)	✗	✓	✗	✗	✗	?	✗	✓	✓	✗
SMS Plus		git	✗	✓	✗	?	✗	?	✗	NC	✓	✗
Osmose		1.6	✗	✓	✗	✗	✗	?	✗	✓	✓	✗
HiSMS		0.01 beta	✗	✗	✗	✗	✓*	?	✗	✗	✗	✗
nemulator		4.4	✗	✓	✗	✗	✗	?	✗	✗	✓	✗
Essgee		git	✗	✓	✗	✗	✗	?	✗	✓	✓	✗
Mobile / ARM
Genesis Plus GX*		libretro core	✗	✓	✓	✓	✗	Very high	✓	NC	✓	✓
Snepulator MS		v23.04-1git	✗	✓	✗	✗	✗	?	✗	✓	✓	✓
FinalBurn Neo		libretro core	✓	✓	✓	✓	✗	?	?	NC	✓	✓
MasterGear		4.9.3	✗	✓	✗	✗	✗	High	✗	✗	✓	~
MasterEmu		4.0.1 git	✗	✓	✗	✗	✗	High	✗	✓	✓	~
MD.emu		1.5.73 (Android) 1.5.46.02 (Pyra)	✗	✓	✗	✗	✗	High	✗	✓	✓	~
WonderDroid Ultra		5.3git	✗	✓	✗	✗	✗		✗	✓	✓	~
PicoDrive		libretro core	✗	✗	✓	✓	✗	Mid	✓	NC	✓	~
GearMasterPlayer		1.0.5	✗	✓	✗	✗	✗	High	✗	✗	✓	~
Consoles
PicoDrive		libretro core 1.93	✗	✓	✓	?	✗	Mid	✓	NC	✓	✓
Genesis Plus GX		libretro core 1.7.5 RC1	✗	✓	✓	?	✗	Mid	✓	NC	✓	✓
SMS Plus GX		libretro core Wii/NGC	✗	✓	✓	✗	✗	Mid	?	NC	✓ (Libretro Core)	✓
PSMS alt+		1.2	✗	✓	✗	✗	✗	High	✗	?	✗	✓
MasterBoy		2.10	✗	✓	✗	✗	✗	Mid	✗	✗	✗	✓
Virtual Console		N/A	✗	✓	✗	✗	✗	Mid	✗	✗	✗	✓
ApprenticeminusDS		0.4.0	✗	✓	✗	✗	✗	Mid	✗	✗	✗	✓
SMS Plus DC		0.2b	✗	✓	✗	✗	✗	Mid	✗	NC	✗	✓
DrSMS		6.0	✗	✓	✗	✗	✗	Mid	✗	✗	✗	~
UltraSMS		2000	✗	✓	✗	✗	✗	Low	✗	~	✗	✓ (GG only)
MasterGear		0.2	✗	✓	✗	✗	✗	Low	✗	✗	✗	~

Accessories

Name	Genesis Plus GX	Kega Fusion	Snepulator	MEKA	BlastEm	PicoDrive
FM Sound Unit	✓	?	?	?	?	?
Light Phaser	✓	?	✓	✓	WIP	?
Paddle Control	✓	?	✓	✓	?	?
Sports Pad	✓	?	WIP	✓	?	?
Sega Graphic Board	✓	?	✓	✓	?	?
Keyboard	✗	?	?	?	?	?
Furrtek's Master Tap	✓	?	?	?	?	?
Floppy Disk Drive	?	?	?	?	?	?
System Converter	✓	?	?	?	?	~
3-D Glasses	?	?	✓	?	?	?
Game Genie	?	?	?	?	?	?
Action Replay	?	?	?	?	?	?
Gear-to-Gear Cable & VS Cable	✗	✗	✗	✗	✗	✗
Bike Handle	✗	✗	✗	✗	✗	✗

From SG-1000

Sega Graphic Board

Also known as Terebi Oekaki. Includes a graphic board attached to a cartridge. Can be used on SG-1000, SC-3000, Sega Mark III, and Japanese / Korean models of Master System. Another version made for the International Master System models was planned to be released and even advertised but was canceled (both ROMs are dumped).

MEKA supports both variants of the Graphic Boards.

Keyboard

Named Sega Keyboard SK-1100. It essentially adds some of the missing features of the SC-3000 to an SG-1000 or Sega Mark III. It is not compatible with the Japanese / Korean models of Master System due to pinout differences in their respective expansion ports.

Kega Fusion, Meka, and MAME support this keyboard. It can also be used with the Japanese version of F-16 Fighting Falcon as well.

Data Recorder SR-1000

Datacorder that allows common cassette tapes to be read and written with the BASIC software from SG-1000, SC-3000, or Sega Mark III. On SG-1000 and Sega Mark III, the presence of a SK-1100 is required, so, it is not compatible with the Japanese Sega Master System. It can be used on:

• C-So! (SG-1000)
• Championship Lode Runner (SG-1000)
• Lode Runner (SG-1000)

MAME supports reading and writing cassette tape images. blueMSX also had planned tape support for their SC-3000 driver as well.

Handle Controller & Bike Handle

Known as SR-400 and BH-400, both are driving controllers compatible with the following games:

• Enduro Racer
• GP World (SG-1000)
• Hang-On
• Hang-On II (SG-1000)
• Monaco GP (SG-1000)
• Safari Race (SG-1000)
• Zippy Race (SG-1000)
• Zoom 909 (SG-1000)

No emulators support these controllers for now.

RAM Adapter

An 8KB RAM Adapter to be used in SG-1000, sold only in Taiwan without a license from Sega. It allows certain MSX1 conversions to be played on the system. While some of the known games were also ported to Sega Mark III, these ones from SG-1000 still require their respective adapter due to the way they were programmed.

Genesis Plus GX, MEKA, and MAME do support this accessory as a form of cartridge mapper.

Master System only

FM Sound Unit

Optional soundboard released for Sega Mark III. Was included by default in Japanese models of the Sega Master System. Features a Yamaha YM2413, which was been used in many MSX games. Some games with FM Sound Unit support were not released in Japan, while others had FM Sound Unit support unused or incomplete, which, for the former, must be activated with manipulation in the system's RAM (e.g.: Pro Action Replay).

Most known emulators such as Kega Fusion, MEKA, MAME, and Genesis Plus GX do support this add-on. Unfortunately, this soundboard was not carried to the Sega Genesis by any means and must be modded by the owner or through flash carts such as Mega Everdrive X7.

Light Phaser

A light gun that was released pretty much everywhere outside Japan. Some games such as Safari Hunt require this accessory to be played.

Kega Fusion, MEKA, MAME, and Genesis Plus GX support Light Phaser controls through Mouse input.

Paddle Control

A dial controller that was released only in Japan. It functions similarly to Taito's Arkanoid / Vaus controller for NES and MSX. Most games that support this controller actually require it.

Kega Fusion, MEKA, MAME, and Genesis Plus GX support Paddle controls through Mouse input. Some games are patched to be playable with a Control Pad or even with Sega Genesis Control Pads.

Sega Sports Pad

A trackball controller that was released only in North America and Japan. The American version is more complete, as it is bigger and has switches that allow it to be used as a Control Pad, while the Japanese version lacks this switch and is smaller. It is only used in Sports Pad Football (also known as Great Football, without Sports Pad support), Sports Pad Soccer (also known as Great Soccer [Cart version], World Soccer and Super Futebol, all of them without Sports Pad support) and Great Ice Hockey.

MEKA, MAME, and Genesis Plus GX support Sports Pad controls through Mouse input.

3-D Glasses

Known as SegaScope 3-D Glasses, it is a 3D glasses set to be used within the Card port (or with a headphone jack in Japanese models of SMS). It works similar, but way better, than Famicom 3D System games.

MEKA and MAME support 3D visuals of all games. Re-releases of Maze Hunter 3D by Sega also support the 3D effects from this game as well. Some games received patches to remove the required 3D glasses support.

Mark III Link Cable

A special cable that connects two Mark III systems through the SK-1100's Printer port. It is solely used by the Japanese version of F-16 Fighting Falcon for its respective 2-player mode.

No known emulator is capable of emulating this feature.

Floppy Disk Drive

An unreleased disk drive add-on that could connect to both International and Japanese models of the Sega Master System. It was supposed to accept 3½-inch disks that could store game(s) and save data, similar to how the Famicom Disk System could do for the Famicom. It should not be confused with the SF-7000 add-on for SC-3000.

Due to a lack of documentation on the unreleased hardware, including the floppy disk's file format, no emulators are capable of emulating it.

Game Gear only

TV Tuner

Perhaps the killer app of all Game Gear accessories, the TV Tuner is a special cartridge that allows the user to watch analog TV signals on a handheld. It also has a mono RCA input that allows devices such as VCR/DVD Players to be displayed. Due to how most countries (by 2010 decade) across the globe switched over to digital TV signals and replaced the former TV mode with 4G mobile internet signals, the main purpose of the TV Tuner is now useless.

Due to the cartridge itself having no actual software (ROM or firmware) inside, it is not emulated for now.

FM Tuner

Working in a similar way to the TV Tuner, the Stereo FM Tuner is an unlicensed special cartridge that allows a Game Gear owner to hear FM radio stations. It was released only in the United States, but it can work in any country that accepts the 87.5 ~ 108.0 MHz bands for FM broadcasting.

Just like the TV Tuner, the cartridge itself has no actual software, so, it is not emulated for now.

Gear-to-Gear Cable

The Gear-to-Gear Cable is a cable that allows two players to compete with each other in several games.

The 3DS Virtual Console emulator, m2engage, allows Gear-to-Gear Cable emulation through Local Play. Alternatively, the Game Gear emulator used in Sonic Origins Plus also allows several Sonic games to be used in their respective Versus modes.

Game Genie

Cheating device that was released by Galoob in North America and (also developed) by Codemasters in Europe. It was released as an official device licensed by Sega, alongside the Sega Genesis version.

Many emulators such as Kega Fusion, Genesis Plus GX, MAME, and MEKA support Game Genie codes as an in-emulator feature, but none of them supports Game Genie as a Lock-On method due to the Game Gear version's ROM being not dumped for years.

Pro Action Replay

Cheating device that was released by Datel in Europe. Unlike Game Genie, it manipulates with both systems' RAM and is not licensed by Sega.

Many emulators such as Kega Fusion, Genesis Plus GX, MAME, and MEKA support Pro Action Replay codes as an in-emulator feature, but none of them supports Pro Action Replay as a Lock-On method due to both Master System and Game Gear versions' respective ROMs being not dumped for years.

X-Terminator

A series of cheating cartridges/discs released across multiple video game systems in Japan. There is one for Game Gear, which has also been sold in the US and certain Mandarin-speaking countries (e.g.: Hong Kong). The code format is similar (if not identical) to the Pro Action Replay ones, affecting the system's RAM values.

Emulicious supports X-Terminator as an in-emulator feature, but it is unknown if it supports the Lock-On method with the X-Terminator ROM itself.

From Sega Genesis

Three and Six Button Control Pad(s)

3 and 6-button control pads that were released for the Sega Genesis. Most third-party variants are compatible with most Master System games (and can even be used on SG-1000/SC-3000), although none of the extra buttons will work beyond B and C.

Only a few homebrew games or ROM hacks make full use of the 3/6 button control pads. At least in their libretro fork, Genesis Plus GX supports several Genesis controllers to be used in Sega 8-bit systems, as long the game itself supports them.

Super Magic Drive

A series of copiers from Front Fareast allows a person to copy game cartridges to floppy disks, allowing the ROM images to run in an emulator. The ROM files are dumped in the .smd format. The copier also allows SNES and PC Engine games to be played as well through physical adapters.

While not directly compatible with the Master System, the BIOS running from these devices runs on Genesis' backward compatibility mode. While they can be playable in emulators, the Master System emulators themselves will not emulate any of the functions made by the hardware itself. Although it is not confirmed if the Super Magic Drive can dump ROMs from Master System cartridges, an unofficial loader made to run Master System ROMs in a real Super Magic Drive was been made by Charles MacDonald.

Hardware quirks

Games with extra RAM

Some cartridges include extra RAM in their cartridge boards. These games are:

• Ernie Els Golf (8KB, Game Gear only)
• BASIC Level II A (512 bytes, SG-1000, SC-3000 and Sega Mark III only)
• BASIC Level II B (1KB, SG-1000, SC-3000 and Sega Mark III only)
• BASIC SK-III (32KB, SG-1000 / Sega Mark III only)
• Desert Speedtrap (8KB, Master System version only)
• Home BASIC (32KB, SG-1000 / Sega Mark III only)
• Othello (2KB)
• The Castle (8KB)
• The Flash (8KB)
• The Terminator (8KB, Master System version only)

Not backward compatible warnings

Two games released in Sega Card, Pit Pot and Hang-On display an incompatibility message if they are played in a real SG-1000/SC-3000 through the Card Catcher. This feature predicts the not backward compatible warning screens from Game Boy Color-only games by more than 15 years.

Some emulators allow the use to force a system to be chosen, such as Genesis Plus GX and MAME, and these screens can be reproduced on them.

Mappers

Just like the NES, both Master System (including games that rely on legacy video modes from SG-1000) and Game Gear support a variety of cartridge mappers that can be used in their respective systems. However, only two mappers are official: The Sega one and a Codemasters one, used in their own cartridges. Many unlicensed cartridges (mostly from South Korea and Taiwan) use their own custom mappers.

Emulators that are updated still to this very day such as MEKA, Genesis Plus GX, MAME, and Emulicious, can handle almost every kind of unlicensed cartridge mapper known to the community. Most of them are used for multicarts that contain original SMS games, SG-1000 games, or even unlicensed MSX1 conversions. Notably, the only unlicensed Western cartridge with a custom mapper is 4 PAK All Action from HES, which was released only in Australia.

Game Gear to Master System hacks

ROM hacks of Game Gear games that allow them to be played in a real Master System or a Sega Genesis through the Power Base Converter. While the main advantage is a bigger (but still restricted) play area, there are more disadvantages to using them, such as a second controller required to mimic the Game Gear's Start button, a weaker color palette, missing animations or sprite zoom, graphical garbage, and no Stereo function.

While not recommended, they can be played on outdated Master System emulators who does not emulate a Game Gear, such as PicoDrive.

MSX1 and Colecovision conversions

Conversions of MSX1 and Colecovision games made by bootleg companies in Taiwan or South Korea (except for Colecovision) or by the community. While made primarily thanks to the legacy video modes inherited from SG-1000, they are optimized for Master System and Game Gear through flash carts such as Master Everdrive and Everdrive GG. They will not work on a Sega Genesis.

Most of these conversions are not playable on SG-1000/SC-3000 with extra RAM and do not work in outdated emulators.

BIOS routine check

International Master System models do have a ROM header routine check. Most games that originated from Japanese-style cartridges do not include this ROM header, which forces the BIOS to give a SOFTWARE ERROR message, regardless from an adapter or through a custom flash cart. The only BIOS that bypasses this check is the one included in Japanese and Korean models. On Game Gear, the Majesco-manufactured models include a BIOS that works in the same way as the TMSS from Sega Genesis, except the routine is performed in the same way as the International Master System models do.

The BIOS from all models can be emulated in Kega Fusion, MAME, Genesis Plus GX, and others, although they are completely optional. MEKA includes an altered version of the v1.3 BIOS that skips the routine check.

Dual language

Some Master System and Game Gear games have dual language support, depending on the hardware's region. Japan, Korea, Taiwan, and Hong Kong use the Japan region, while every other country uses the International (English) region. This behavior may be updated in time with a region switch and such behavior can be done in emulators as well (results vary between games).

Forced flickering

A trait used in several Game Gear games that makes graphical objects flicker constantly in order to avoid damage to the LCD screen thanks to screen burn-in. It is used in Ayrton Senna's Super Monaco GP II for example.

Since this is an issue that affects only the real hardware, all known Game Gear emulators do not include an internal fix for these games.

93C46 EEPROM

A 128-byte EEPROM is used in several Game Gear cartridges. All games are licensed baseball games that make use of the EEPROM to hold custom team data and/or save Pennant Mode progress:

• The Majors Pro Baseball
• World Series Baseball / Pro Yakyuu GG League
• World Series Baseball '95 (the Japanese version, Hideo Nomo no World Series Baseball, uses generic SRAM)

Several outdated Game Gear emulators do not emulate this type of SRAM, which also makes the game not initialize properly or not boot at all.

Stereo Music

A function used in most Game Gear games, it adds channel audio panning to the handheld's sound chip.

Most known Game Gear emulators support this function.

Hardware variants

Several emulators such as MAME and Genesis Plus GX emulates dedicated hardware quirks from multiple variants of both Master System and Game Gear. Here are all the models that can be related to Master System and Game Gear:

SG-1000

The earlier revision of Sega Mark III. Based on Colecovision after Sega gave up on the plans of distributing them in Japan around 1982. Released in 1983 in Japan and Oceania. Does not include regional differences in software, nor does include a BIOS. All games can be played on Sega Mark III and most of them can be played on the Japanese Sega Master System without problems.

SG-1000 II

A revised version of the SG-1000. It combines the VDP and SN76489 in one single chip. A prototype diagnosis program, SG-1000 M2 Check Program, can be used to test hardware problems and emulators' accuracy.

Sega Mark III (Japan)

The first revision of the system. Released in 1985 in Japan, with South Korea and Taiwan receiving it in 1986. Supports almost everything related to SG-1000, although software released only to SC-3000 still works only on SC-3000. Does not have a BIOS and cannot play music on FM and PSG at the same time. SG-1000 games are played with a darker color palette.

Sega Master System (International)

Released in 1986 in the USA, Australia plus minor European countries, 1987 in mainland Europe, and 1989 in Brazil. Has a different cartridge pinout, a different expansion port pinout (which is canonically unused), and includes a BIOS that prevents unlicensed software from running. Cannot run SG-1000 cartridges and cards (even with an adapter, which must be done by DIY projects) without applying a ROM header in the game. Some Japan-only games do not include this required ROM header, but one exception, Woody Pop, actually runs. Cannot use the FM Sound Unit unless through hardware mods.

Sega Master System (Japan)

Released in 1987 in Japan and 1989 in South Korea. Supports most SG-1000 titles, except the ones that require the SK-1100 (expansion port pinout is from the International model). Includes a BIOS, but it does not check a ROM header. It also includes the FM Sound Unit built-in. SG-1000 games are still being played with a darker color palette.

Power Base Converter (USA) / Mega Adaptor (Japan) / Master System Converter (International)

Released in 1989 in Japan plus the USA, 1990 in Europe plus Brazil. Supports about 90% of the Master System library through an adapter for Sega Genesis, which relies on backward compatibility. No BIOS is included, region detection is done by the Genesis itself. It lacks the legacy video modes from SG-1000, which turns SG-1000 games (or SMS games that rely on legacy video modes) unplayable without graphics. Does not include FM Sound Unit, which can only be done with hardware mods or with unlicensed variants of the adapter. It is not directly compatible with Nomad, Genesis 3, or most Mega Drive clones and is totally incompatible with any Genesis system with a 32x.

Sega Master System II (International)

Released in 1990 in the US, 1991 in Europe plus Australia, and 1992 in Brazil. Supports only cartridges, includes a BIOS with Alex Kidd in Miracle World (Sonic the Hedgehog in later models), lacks a Reset button, and has improvements on the VDP. Some Brazilian-only games can run only in this model.

Samsung Gam*boy II / Aladdin Boy (Japan)

Released between 1991~1993 in South Korea by Samsung. Supports games on SG-1000 cartridge pinout, runs games within the "Japan" region, FM Sound Unit is not present, and includes a BIOS with a Korean version of Alex Kidd in Miracle World (also replaced with Sonic the Hedgehog in Aladdin Boy) that does not check ROM headers. Otherwise identical to International SMS II.

Sega Game Gear (International and Japan)

Enhanced VDP and sound features. Does not include a BIOS (save for the Majesco model). The screen area is lower than SMS and does not include the FM Sound Unit built-in. Can run SG-1000 games with external adapters on real hardware (Master Gear Converter is not enough and this doubles even more if the game is only in the Card format).

Arcade

Several Master System-based Arcade boards, mainly produced by Sega themselves, do exist:

• Sega System E (actual improvements on sound)
• Sega Shooting Zone
• Sega Mega-Tech (runs converted Master System games through the backward compatibility inherited from Genesis)
• Sega Mega Play (does not run Master System games, but the BIOS itself runs in this mode, again, through the backward compatibility inherited from Genesis)

Additionally, several bootleg arcade/hotel boxes such as Super Game were been reported to be sold in South Korea and Japan, without being licensed by Sega. Some of these also include SG-1000 games or even MSX1 conversions built-in.