Sega Master System

From Sega Retro

(Redirected from Master System)

Master System logo.svg


Fast Facts on the Sega Master System

Made by: Sega
Variants: Sega Mark III, Sega Master System II, Sega Game Box 9, Tectoy Master System Super Compact, Super Gam*Boy, Super Gam*Boy II
Processor: Zilog Z80

Release Date RRP Code
Sega Master System JP 1987-10-18 ¥16,800 MK-2000
Sega Master System US 1986-10 $150 (MS)  ?
Sega Master System UK 1987-08 £99.95  ?
Sega Master System FR 1987-09 990FF  ?
Sega Master System DE 1986-10 298DM  ?
Sega Master System IT 1986-11 300,000£  ?
Sega Master System AU 1986 $?  ?
Sega Master System BR 1989-09-04 $1,500  ?
Sega Master System KR 1989-04 ₩119,000  ?
Sega Master System AR 19xx $?  ?
Sega Master System ZA 19xx R ?  ?

The Sega Master System (セガ・マスターシステム) or SMS, is a cartridge-based video game console manufactured by Sega. It is a rebranding of the Sega Mark III intended for western markets, which in turn was a successor to the SG-1000 and SG-1000 II. In South Korea the Master System was distributed by Samsung and known as the Gam*Boy (겜보이) and later Aladdin Boy (알라딘 보이). It was codenamed the Sega Mark IV during development.

The Sega Master System was the first of Sega's consoles to see widespread distribution, and went head-to-head with Nintendo's Famicom/NES across the world. Though it was unsuccessful at dethroning Nintendo in Japan and North America, the Master System was able to outperform other rivals (notably the Atari 7800) in those regions. The Master System found its greatest success in Europe and South America, regions where it outsold the NES. Worldwide, it hit second place in the third generation of video game consoles, selling more than 14.8 million units worldwide, including more than 6.8 million in Europe, 5 million in Brazil, 2 million in the United States, and 1 million in Japan. This helped pave the way for the more successful Sega Mega Drive.

The "Sega Master System" name is a relatively new invention, adopted towards the end of the 1980s after a release in Japan, Australia and a series of price drops and "improved" bundles forced the "Master System" name into use. During its first few years of service, the Master System was simply known as the Sega System or in some countries, just the Sega. It has also been (incorrectly) referred to as the Sega Master or Master. Depending on the package, the console may have also been referred to as the Sega Base System, Sega Super System, Sega Video Game System or Sega SegaScope 3-D System, with the console unit itself being referred to as the Sega Power Base.



Main article: Sega Master System Models

Master System

The original 1986 model Sega Master System took a radically different approach to its outward design to the Mark III, released a year prior. The main unit, commonly referred to as the "Power Base" is a black 3D trapezium with red/orange highlights, measuring 143/8 inches in width, 65/8 inches deep and 23/4 inches in height. After a one-inch base, the machine is formed upward and inward to form the cartridge slot plateau.

The Master System takes most of its design cues from the Nintendo Entertainment System, released in late 1985, with detachable controllers and power and reset buttons, though like prior Sega consoles (and virtually all cartridge-based systems going forward), is a top-loading machine. It also contains a card slot for the handful of games distributed on Sega Card, and curiously, a diagram or vague instructions as to how the system works (i.e. insert a cartridge, power the system on, and use the control pads to manipulate an image on a television screen). The Master System also has a built-in "pause" button for stopping play.

The Master System has an introduction screen which appears each time the system is turned on (with or without a game inserted). The Sega logo slowly "slides" into view mid-screen (with accompanying sound effect), and the text "Master System" appears underneath, with the two-tone "Sega" tune also being played during this sequence.

Unlike the NES, the Master System displays an instructional screen if the system is turned on without having a cart or card inserted, though as Sega moved to using built-in software, the console instead began to automatically load the built-in game instead. Early original Master Systems also contain the "easter egg" Snail Maze minigame.

The 1987 Japanese release, whose design was also brought to South Korea, makes a number of important changes. Aside from adjusting the the cartridge slot, it has the Mark III's FM Sound Unit built-in from the get go, and supports the 3D Glasses without the need for an adapter (which usually plugs into the card slot).

Master System II

After a period of decline and the rise of the newly-released Sega Mega Drive, Sega constructed the Sega Master System II for overseas markets. There is virtually no resemblence to the earlier model, opting for smooth curves and rounded corners more akin to the Mega Drive, and is a great deal smaller (and, as a result, cheaper to manufacture).

The Master System II removes many features (usually unpopular ones) in an effort to cut costs. There is no card port (and by extension, no 3D Glasses support), the unused expansion port was removed and the reset button has been omitted in favour of a larger pause button. The swinging, hinged cartridge slot doors of the original model are replaced with a sliding cover (which cannot be closed with a cartridge inserted), and the number of video output options reduced (usually to just RF). Also missing is a power LED and the BIOS screen introducing the console when powered on.

Each region has its own set of cosmetic differences. In Brazil the system is known as the Master System III Compact, and in South Korea it was released twice, first as the Super Gam*Boy II and later the Aladdin Boy.

All Master System IIs either included Alex Kidd in Miracle World as a built-in game, or Sonic the Hedgehog, which arrived in 1991.



  • 8-bit Zilog Z80
    • 3546893Hz for PAL/SECAM, 3579545Hz for NTSC


  • VDP (Video Display Processor) derived from Texas Instruments TMS9918
    • Up to 32 simultaneous colors (16 for sprites, 16 for background) available from a palette of 64 (can also show 64 simultaneous colors using programming tricks)
    • Screen resolutions 256x192 and 256x224. PAL/SECAM also supports 256x240
    • 8x8 pixel characters, max 488 (due to VRAM space limitation)
    • 8x8 or 8x16 pixel sprites, max 64
    • Horizontal, diagonal, vertical, and partial screen scrolling


  • Sound (PSG): Texas Instruments SN76489
    • 4 channel mono sound
    • 3 sound generators, 4 octaves each, 1 white noise generator
  • Sound (FM): Yamaha YM-2413
    • 9 channel mono 2-operator FM sound
    • built into Japanese Master System
    • available as plug-in module for Mark III
    • supported by certain games only


  • ROM: 64 Kbits (8KB) to 2048 Kbits (256kB), depending on built-in game
  • Main RAM: 64 Kbits (8KB)
  • Video RAM: 128 Kbits (16KB)

Game Slot

  • Game Card slot (Mark III and original Master System only)
  • Game Cartridge slot
    • Japanese and South Korean consoles use 44-pin cartridges, same shape as the SG-1000
    • Western consoles use 50-pin cartridges with a different shape
    • The difference in cartridge style is most likely a form of regional lockout
  • Expansion slot



RF Converter: MGB3-VU3401, 8E388        
PCB Component Side Markings: (c) SEGA 1988         
:       SEGA (R) M4  POWERBASE / NTSC  171-5533-01       
:       837-6629  19 AUG 1988         
CON2: 35 Pin Card Slot  209-5020 K16R         
CON3: 50 Pin Cartridge Slot  PSB4D255-4R1 M18R         
CON4: 50 Pin Card Edge         
IC1:  Zilog Z0840004PSC Z80CPU 8828 SL0965         
IC2:  0821EX SEGA MPR-11460 W46         
IC3:  NEC JAPAN D4168C-20 8829P5007         
IC4:  SEGA (R) 315-5216 120U 8820 Z79         
IC5:  SEGA 315-5124 2602B 84 18 89 B         
IC6:  NEC JAPAN D4168C-15-SG 8828XX215         
IC7:  NEC JAPAN D4168C-15-SG 8828XX215
IC9:  SONY 8M09 CXA1145

SMS Control Pad Information:

  • female plug on end view:
5 4 3 2 1 
 9 8 7 6        
  • pin 1: Up
  • pin 2: Down
  • pin 3: Left
  • pin 4: Right
  • pin 5: No Connection
  • pin 6: Button 1 (Start)
  • pin 7: No Connection
  • pin 8: Common (Ground)
  • pin 9: Button 2


North America

Though the SC-3000 had been distributed across Europe, Asia, Australia and New Zealand, North America was new ground for Sega, and the company felt that the Sega Mark III name would fail to attract customers. The console was therefore completely redesigned, and the new "Sega System" first appeared at CES in June 1986. It was announced for a September release, although it didn't actually make it to store shelves until October.

Initially two bundles of the console were sold in this region - the cheaper "Sega Base System" (containing just a Power Base (the console unit) and a control pad) and the "Sega Master System" (which also included a second control pad and a Light Phaser). The latter bundle eventually proved to be more popular, and as future bundles intended to include more and more items to fight competition from Nintendo, the "Sega Master System" name was applied it to all future products, eventually dropping the term "Sega System" entirely.

Nintendo had control of 90% of the North American video game market at the time, and Sega struggled to get a foothold in the region. After several months of poor sales, Hayao Nakayama, then CEO of Sega, decided to invest less money into marketing the Master System, inevitably selling the North American rights to Tonka in 1988. The move was considered a very bad one, since Tonka had never marketed a video game console and were clueless how to step up their game, hence its popularity continued to decline.

By 1990, Sega had released the Sega Mega Drive (Sega Genesis) and felt the need to take back the rights from Tonka for the SMS. They soon created the cost-reduced Sega Master System II, a newer console which was smaller and sleeker but which, to keep production costs low, lacked several features that had been present on the original. Sega did everything in its power to market the system, but nothing came out of it. By 1991, the Master System's sales were virtually nonexistent in North America, and production ceased.

Though the Master System was more technically advanced in some ways than the NES, it did not attain the same level of popularity among consumers in the United States. The licensing agreement that Nintendo had with its third-party game developers may have had an impact as well; the agreement stated, in effect, that developers would produce games for the NES only. However, Sega did have the advantage of being able to pluck titles from their ever-growing arcade game library at the time, and so was able to build up a strong library of exclusive Master System titles.

The Master System sold 125,000 consoles in the first four months, while in the same period, the NES would net 2,000,000. It is likely that Sega achieved better results with the Master System than Atari did with their Atari 7800 console, released in the same year.

In Canada, the Master System was distributed by Irwin Toy, though many games were imported from the US.


Pressure had been applied to Sega from the minute they entered the home console market in Japan. The SG-1000 and SG-1000 II were less successful than expected, fighting a losing battle against the MSX computer standard and the rise of the Nintendo Famicom. Faced with market defeat, Sega released the much improved Sega Mark III in the hopes of gaining a bigger share of the market.

But the Sega Mark III also failed to sell in the volumes Sega expected. In a last ditch effort, Sega brought the redesigned Sega Master System seen in North America to the Japanese audience in late 1987. The Japanese system is slightly superior in design - it contains the Mark III FM Sound Unit (missing from western versions), a port to connect the 3-D glasses directly to the console, and is fully backwards compatible with the SG-1000 (like the Mark III). Differing cartridge sizes meant this was not possible outside Japan and Korea.

The Master System performed slightly better than the Sega Mark III, but faced stiff competition with newer systems, including Sega's own Mega Drive, which debuted in October 1988. The Master System was essentially dead by the end of 1988, with one new release in December of that year (Chouon Senshi Borgman) and the final release arriving in February 1989 (Bomber Raid).

Japanese Master Systems are quite difficult to spot, even though the cartridge size is smaller. They can be identified by the text on the left hand side of the unit - western models read "Master System/Power Base", while Japanese systems simply read "Master System".


At the time, Europe was still a divided continent when it came to video games. Most consumers (especially within the UK) played games through home computers, such as the ZX Spectrum and Commodore 64. American video game consoles were sold in the region, but were not marketed heavily, leaving a big gap for Sega to fill.

The Master System arrived in Europe at different points, starting with Germany in October 1986 before seeing a more wider release in the United Kingdom, France and Italy during Autumn 1987. The PAL model was at the time, virtually identical to the North American model, however obviously output a PAL signal rather than an NTSC one. Sega distributed the consoles themselves, making a much bolder effort than Nintendo, and selling the Master System in regions Nintendo had neglected. The Europeans hence garnered lots of third party support for the SMS, forcing Nintendo to obtain licensing for some popular SMS titles in that market.

In the United Kingdom, the initial Master System release sold for £99.95 and came bundled with the card version of Hang-On.

The redesigned Sega Master System II was also released in Europe, however the colouring is slightly different; European SMS IIs are black, while their North American counterparts are grey.

Unlike the rest of the world, the Master System was able to outsell the NES in Europe, mainly due to the numerous poor marketing decisions and delays from Nintendo's European distributors (which arguably still continue to this day). The Master System was supported until 1996 in Europe, but was finally discontinued so Sega could concentrate on the Sega Saturn. Many Master System games were exclusive to Europe, and the console established a large user base to market the even more successful Sega Mega Drive to.


Brazil was one of the SMS' most successful markets. The Master System was marketed by Tec Toy, Sega's Brazilian distributor, and as there was limited competition, became the console of choice. Further re-releases of the console such as the Sega Master System III were released, and several games were translated into Portuguese or localised for a Brazilian audience (for example, Wonder Boy in Monster Land featured Turma da Mônica, the main character from a popular children's comic-book in Brazil).

Later in its life, Sega Game Gear games had been ported to the Master System, and several original Brazilian titles were made for the console. Tec Toy also produced a licensed version of the wildly popular fighting game Street Fighter II in 1997, one of the most technically impressive titles for the system.

The Sega Master System is still being produced in Brazil, though systems with cartridge slots faded away by the mid-2000s. For more information see Tectoy Master System.

South Korea

At the time, tensions between Japan and other Asian countries meant that Sega could not market the Sega Master System themselves. Instead, Samsung were put in charge, renaming the system as the Gam*Boy and repackaging/translating software and hardware in 1989. There are several Master System games exclusive to South Korea, but rampant piracy means many of these games are also unlicensed. Many of these games are MSX ports, and so use the SG-1000 video modes as opposed to the Master System's more sophisticated video modes.

The version of the system released in South Korea is identical to the Japanese Master System, albeit without FM audio. It was advertised to retail at ₩119,000 and included two controllers and a "2MB Compatibility Pack".

South Korean cartridges are of the same form factor and pinout as Japanese cartridges, and so both regions are interchangeable with one another. South Korean control pads however have a more rounded look, and employ a different type of D-pad, similar to Nintendo's. Like its western counterparts, the console was redesigned and sold as the Gam*Boy II / Aladdin Boy, but it employed a completely different color scheme.


The Master System also saw a release in other parts of Asia, with the console being very similar to the redesigned Japanese model. The only major difference is that some regions required a PAL signal, while others an NTSC one. It is otherwise fully compatible with the Japanese game library.


Can Game Gear games be played on the SMS?

The Game Gear can run SMS carts, of course, but that is due to intentional backwards compatibility of the GG to the SMS, and such does not work in reverse. The only hardware difference known between the two on a chip level is that the GG can define 4096 possible colors, while the SMS can only define 64 colors. As the GG has more colors, it has a different method of setting each of the color registers than the SMS did: The SMS color can be determined by one byte and hence only needed one register, whereas a number from 0 to 4095 needs two bytes, and so the GG VDP has two color registers. Game Gear games which use the expanded graphics mode will run on an SMS, but with scrambled colors; the lack of a "Start" button also prevents many Game Gear games from being played. Several Game Gear games were straight ports of their SMS counterparts and will run through the use of a flash cart or homemade cartridge adapter.

Sega RGB Cable

In France, the original Master System (and the SMS II, which had the A/V port instead of RF jack) were sold with an RGB lead (model 3085). One end plugs into the SMS, the other into the SCART/Peritel socket on a TV, via a small box in the lead, labeled 'Adapteur R.V.B.'. As it utilizes RGB, it gives a sharper and more vibrant picture compared to RF or composite video. The box contains a small PCB, the purpose of which is to provide the blanking and function switching signals, so that the TV can automatically switch to RGB input.


See List of Master System games for a complete list.

Launch Titles


North America

United Kingdom

Promotional Material

Print Advertisements

Television Advertisements

External links

Sega Game Systems (by console generation)
2nd Gen   SG-1000 | SG-1000 II | SC-3000
3rd Gen   Mark III | Master System | Game Gear
4th Gen   Mega Drive/32X/CD | Pico
5th Gen   Saturn
 6th Gen   Dreamcast
Sega Master System Hardware
 Master System Variations   Asia | North America | Europe | South America

Sega Mark III | Sega Game Box 9 | Tectoy Master System Girl | Tectoy Master System Super Compact | Kiosk

Add-ons   Telecon Pack | FM Sound Unit
Game Controllers   SJ-152 | Control Pad | 3-D Glasses | Control Stick | Handle Controller | Light Phaser | Paddle Control | Rapid Fire Unit | Sports Pad | SG Commander
Misc. Hardware   Action Replay | Card Catcher | Action Case | Freedom Connection | Playkit
Unreleased Accessories   Floppy Disk Drive
Consoles on a Chip   Arcade Gamer Portable | Coby TF-DVD560 | DVD Karaoke Game DVT-G100 | Fun Play 20-in-1 | Master System 3 | Master System Evolution | Master System Handy | PlayPal Plug & Play | Poga | Time Plug & Play on TV