Sega Genesis

Sega Genesis / Mega Drive

Top: Original Japanese Mega Drive Bottom: Sega Genesis Model 2 Other variations are pictured under Variations below
Manufacturer	Sega
Type	Home video game console
Generation	Fourth generation
Release date	JP: October 29, 1988 NA: August 14, 1989 KOR: August 1990 PAL: September 1990 BRA: September 1, 1990
Retail availability	1988–1997 (Sega) 1988–present (overall) NA: Ongoing (AtGames) EU: Ongoing (AtGames, Blaze Europe) BRA: Ongoing (Tec Toy)
Discontinued	WW: 1997 (Sega) NA
Units sold	Sega: 30.75 million Tec Toy: 3 million Majesco: 1.5 million (projected)
Media	ROM cartridge
CPU	Motorola 68000 @ 7.6 MHz Zilog Z80 @ 3.58 MHz
Display	Progressive: 320x224, 256x224 (NTSC) or 320x240, 256x240 (PAL) pixels, 512 color palette, 61 colors on-screen Interlaced: 320x448, 256x448 (NTSC) or 320x480, 256x480 (PAL)
Sound	Yamaha YM2612 Texas Instruments SN76489
Online services	Sega Meganet Sega Channel XBAND
Best-selling game	Sonic the Hedgehog (15 million)
Backward compatibility	Master System (Through use of the Power Base Converter peripheral)
Predecessor	Master System
Successor	Sega Saturn

Introduction

The Sega Genesis, known as the Mega Drive in regions outside of North America, is a 16-bit home video game console developed and sold by Sega. The Genesis was Sega's third console and the successor to the Master System. Sega released the console as the Mega Drive in Japan in 1988, followed by North America as the Genesis in 1989. In 1990, the console was distributed as the Mega Drive by Virgin Mastertronic in Europe, Ozisoft in Australasia, and Tec Toy in Brazil. In South Korea, the systems were distributed by Samsung as the Super Gam*Boy and later the Super Aladdin Boy.

Designed by an R&D team supervised by Hideki Sato and Masami Ishikawa, the hardware was adapted from Sega's System 16 arcade board, centered on a Motorola 68000 processor as the CPU, a Zilog Z80 as a sound controller, and a video system supporting hardware sprites, tiles, and scrolling. The system plays a library of more than 900 games created by Sega and a wide array of third-party publishers and delivered on ROM-based cartridges. The Genesis has benefited from several add-ons, including a Power Base Converter to play Master System games, as well as multiple first and third party licensed variations of the console. Sega created two network services to support the Genesis: Sega Meganet and Sega Channel.

In Japan, the Mega Drive did not fare well against its two main competitors, Nintendo's Super Famicom and NEC's PC Engine, but it achieved considerable success in North America, Brazil, and Europe. Contributing to its success were its library of arcade game ports, the popularity of Sega's Sonic the Hedgehog series, several popular sports franchises, and aggressive youth marketing that positioned the system as the cool console for adolescents. The release of the Super Nintendo Entertainment System two years after the Genesis resulted in a fierce battle for market share in the United States and Europe that has often been termed as a "console war" by journalists and historians. As this contest drew increasing attention to the video game industry among the general public, the Genesis and several of its highest-profile games attracted significant legal scrutiny on matters involving reverse engineering and video game violence. Controversy surrounding violent games such as Night Trap and Mortal Kombat led Sega to create the Videogame Rating Council, a predecessor to the Entertainment Software Rating Board.

30.75 million first-party Genesis units were sold worldwide. In addition, Tec Toy sold an estimated three million licensed variants in Brazil, Majesco projected it would sell 1.5 million licensed variants of the system in the United States, and much smaller numbers were sold by Samsung in South Korea. By the mid-2010s, licensed third-party Genesis rereleases were still being sold by AtGames in North America and Europe. Many games have been rereleased in compilations or on online services such as the Nintendo Virtual Console, Xbox Live Arcade, PlayStation Network, and Steam. The Genesis was succeeded in 1994 by the Sega Saturn.

Technical specifications

European Mega Drive mainboard

The main microprocessor is a 16/32-bit Motorola 68000 CPU clocked at 7.6 MHz. The console uses a Zilog Z80 sub-processor, mainly used to control the sound hardware and provide backward compatibility with the Master System. The system has 72 kB of RAM, 64 kB of video RAM, and can display up to 61 colors at once from a palette of 512. The games are in ROM cartridge format and inserted in the top.

The system produces sound using a Yamaha YM2612 FM synthesizer and a Texas Instruments SN76489 PSG; the latter is integrated with the Video Display Processor (VDP). The Z80 processor is primarily used to control both sound chips to produce stereo music and sound effects. Most revisions of the original system contain a discrete YM2612 and a separate YM7101 VDP; the functionality of these two chips was later integrated into a single custom ASIC (FC1004) for the model 2 and later revisions.

The back of the model 1 console provides a radio frequency output port (designed for use with antenna and cable systems) and a specialized 8-pin DIN port, both of which provide video and audio output. Both outputs produce monophonic sound; a headphone jack on the front of the console produces stereo sound. On the model 2, the DIN port, radio frequency output port, and headphone jack are replaced by a 9-pin mini-DIN port on the back for composite video, RGB and stereo sound, and the standard RF switch. Earlier model 1 consoles have a 9-pin extension port, although this was removed in later production runs and is absent in the model 2. An edge connector on the bottom-right of the console allows it to be connected to a peripheral.

Peripherals

Sega Genesis six-button controller

The standard controller features a rounded shape, a directional pad, three main buttons, and a "start" button. Sega later released a six-button version in 1993. This pad is slightly smaller and features three additional face buttons, similar to the design of buttons on some popular arcade fighting games such as Street Fighter II. The third model of the controller, MK-1470 was released with the Sega Genesis Model 3, with a switch between Normal, Turbo, and Slow while also having the Mode button. Sega released a wireless revision of the six-button controller, the Remote Arcade Pad.

The system is backward compatible with the Master System. The first peripheral released, the Power Base Converter (Master System Converter in Europe), allows Master System games to be played. A second model, the Master System Converter 2, was released only in Europe for use with the Mega Drive II.

Other peripherals were released to add functionality. The Menacer is a wireless, infrared light gun peripheral used with compatible games. Other third parties created light gun peripherals for the Genesis, such as the American Laser Games Pistol and the Konami Justifier. Released for art creation software, the Sega Mega Mouse features three buttons and is only compatible with a few games, such as Eye of the Beholder. A foam-covered bat called the BatterUP and the TeeVGolf golf club were released for both the Genesis and SNES.

Sega Power Base Converter on a model 1 Genesis

In November 1993, Sega released the Sega Activator, an octagonal device that lies flat on the floor and translates the player's physical movements into game inputs. Several high-profile games, including Mortal Kombat and Street Fighter II: Special Champion Edition, were adapted to support the peripheral. The device was a commercial failure, due mainly to its inaccuracy and its high price point. IGN editor Craig Harris ranked the Sega Activator the third worst video game controller ever made.

Both EA and Sega released multitaps to allow more than the standard two players to play at once. Initially, EA's version, the 4 Way Play, and Sega's adapter, the Team Player, only supported each publisher's games. In response to complaints about this, Sega publicly stated, "We have been working hard to resolve this problem since we learned of it", and that a new Team Player which would work with all multitap games for the console would be released shortly. Later games were created to work on both the 4 Way Play and Team Player. Codemasters also developed the J-Cart system, providing two extra ports on the cartridge itself, although the technology came late in the console's life and is only featured on a few games. Sega planned to release a steering wheel peripheral in 1994, and the Genesis version of Virtua Racing was advertised as being "steering wheel compatible," but the peripheral was cancelled.

Network services

Sega Mega Modem peripheral, which allowed access to the Sega Meganet service

In its first foray into online gaming, Sega created Sega Meganet, which debuted in Japan on November 3, 1990. Operating through a cartridge and a peripheral called the "Mega Modem," this allowed Mega Drive players to play a total of seventeen games online. A North American version, dubbed "Tele-Genesis," was announced but never released. Another phone-based system, the Mega Anser, turned the Japanese Mega Drive into an online banking terminal.

In 1994, Sega started the Sega Channel, a game distribution system using cable television services Time Warner Cable and TCI. Using a special peripheral, Genesis players could download a game from a library of fifty each month and demos for upcoming releases. Games were downloaded to internal memory and deleted when the console was powered off. The Sega Channel reached 250,000 subscribers at its peak and ran until July 31, 1998, well past the release of the Sega Saturn. However, the Sega Channel received most negative reviews.

In an effort to compete with Sega, third-party developer Catapult Entertainment created the XBAND, a peripheral which allowed Genesis players to engage in online competitive gaming. Using telephone services to share data, XBAND was initially offered in five U.S. cities in November 1994. The following year, the service was extended to the SNES, and Catapult teamed up with Blockbuster Video to market the service, but as interest in the service waned, it was discontinued in April 1997.

Sega Virtua Processor

The graphics produced by the Sega Virtua Processor are comparable to those of Nintendo's Super FX chip.

On the Super NES, companies could add enhancement chips to cartridges to increase the console's capabilities and produce more advanced graphic; for example, the launch game Pilotwings contained a digital signal processor. Later, the Super FX chip was designed to offload complex rendering tasks from the main CPU. It was first used in Star Fox, which renders 3D polygons in real time, and Super Mario World 2: Yoshi's Island demonstrates rotation, scaling, and stretching of individual sprites and manipulates large areas of the screen.

Sega began work on an enhancement chip to compete with the Super FX, resulting in the Sega Virtua Processor. This chip enables the Genesis to render polygons in real time and provides an "Axis Transformation" unit that handles scaling and rotation. Virtua Racing, the only game released with this chip, runs at a significantly higher and more stable frame rate than similar games on the SNES. The chip was expensive to produce, and increased the cost of the games that used it. At US$100, Virtua Racing was the most expensive Genesis cartridge ever produced. Two other games, Virtua Fighter and Daytona USA, were planned for the SVP chip, but were instead moved into the Saturn's launch line-up. There were plans to sell the SVP chip as a separate upgrade module for the Genesis, but this module was never released.

Add-ons

Genesis model 2 with a Sega CD 2 and 32X add-ons attached

In addition to accessories such as the Power Base Converter, the Sega Genesis supports two add-ons that each support their own game libraries. The first is the Sega CD (known as the Mega-CD in all regions except for North America), a compact disc-based peripheral that can play its library of games in CD-ROM format. The second is the Sega 32X, a 32-bit peripheral which uses ROM cartridges and serves as a pass-through for Genesis games. Sega produced a custom power strip to fit the peripherals' large AC adapters. Both add-ons were officially discontinued in 1996.

Sega CD

By 1991, compact discs had gained in popularity as a data storage device for music and software. PCs and video game companies had started to make use of this technology. NEC had been the first to include CD technology in a game console with the release of the TurboGrafx-CD add-on, and Nintendo was making plans to develop its own CD peripheral as well. Seeing the opportunity to gain an advantage over its rivals, Sega partnered with JVC to develop a CD-ROM add-on for the Genesis. Sega launched the Mega-CD in Japan on December 1, 1991, initially retailing at JP¥49,800. The CD add-on was launched in North America on October 15, 1992, as the Sega CD, with a retail price of US$299; it was released in Europe as the Mega-CD in 1993. In addition to greatly expanding the potential size of its games, this add-on unit upgraded the graphics and sound capabilities by adding a second, more powerful processor, more system memory, and hardware-based scaling and rotation similar to that found in Sega's arcade games. It provided battery-backed storage RAM to allow games to save high scores, configuration data, and game progress.

Shortly after its launch in North America, Sega began shipping the Sega CD with the pack-in game Sewer Shark, a full motion video (FMV) game developed by Digital Pictures, a company that became an important partner for Sega. Touting the benefits of the CD's comparatively vast storage space, Sega and its third-party developers produced a number of games for the add-on that include digital video in their gameplay or as bonus content, as well as re-releasing several cartridge-based games with high-fidelity audio tracks. In 1993, Sega released the Sega CD 2, a smaller and lighter version of the add-on designed for the Genesis II, at a reduced price compared to the original. A limited number of games were later developed that use both the Sega CD and the Sega 32X add-ons.

The Mega-CD sold only 100,000 units during its first year in Japan, falling well below expectations. Although many consumers blamed the add-on's high launch price, it also suffered from a tiny software library; only two games were available at launch. This was due in part to the long delay before Sega made its software development kit available to third-party developers. Sales were more successful in North America and Europe, although the novelty of FMV and CD-enhanced games quickly wore off as many of the system's later games were met with lukewarm or negative reviews. In 1995, Sega announced a shift in focus to its new console, the Saturn, and discontinued all advertising for Genesis hardware, including the Sega CD. The add-on sold 2.24 million units worldwide.

Sega 32X

With the release of the Sega Saturn slated for 1995, Sega began to develop a stop-gap solution that would bridge the gap between the Genesis and the Saturn, and would serve as a less expensive entry into the 32-bit era. At the Winter Consumer Electronics Show in January 1994, Sega of America research and development head Joe Miller took a phone call from Nakayama, in which Nakayama stressed the importance of coming up with a quick response to the Atari Jaguar. One potential idea for this came from a concept from Sega Enterprises, later known as "Project Jupiter," an entirely new independent console. Project Jupiter was initially slated to be a new version of the Genesis, with an upgraded color palette and a lower cost than the upcoming Saturn, as well as with some limited 3D capabilities thanks to integration of ideas from the development of the Sega Virtua Processor chip. Miller suggested an alternative strategy, citing concerns with releasing a new console with no previous design specifications within six to nine months. At the suggestion from Miller and his team, Sega designed the 32X as a peripheral for the existing Genesis, expanding its power with two 32-bit SuperH-2 processors. The SH-2 had been developed in 1993 as a joint venture between Sega and Japanese electronics company Hitachi. At the end of the Consumer Electronics show, with the basic design of the 32X in place, Sega Enterprises invited Sega of America to assist in development of the new add-on.

Although the new unit was a stronger console than originally proposed, it was not compatible with Saturn games. Before the 32X could be launched, the release date of the Saturn was announced for November 1994 in Japan, coinciding with the 32X's target launch date in North America. Sega of America now was faced with trying to market the 32X with the Saturn's Japan release occurring simultaneously. Their answer was to call the 32X a "transitional device" between the Genesis and the Saturn. This was justified by Sega's statement that both platforms would run at the same time, and that the 32X would be aimed at players who could not afford the more expensive Saturn.

The 32X was released in November 1994, in time for the holiday season. Demand among retailers was high, and Sega could not keep up orders for the system. More than 1,000,000 orders had been placed for 32X units, but Sega had only managed to ship 600,000 units by January 1995. Launching at about the same price as a Genesis console, the price of the 32X was less than half of what the Saturn's price would be at launch. Notwithstanding the lower priced console's positioning as an inexpensive entry into 32-bit gaming, Sega had a difficult time convincing third-party developers to create games for the new system. After an early run on the peripheral, news soon spread to the public of the upcoming release of the Sega Saturn, which would not support the 32X's games. The Saturn was released on May 11, 1995, four months earlier than its originally intended release date of September 2, 1995. The Saturn, in turn, caused developers to further shy away from the console and created doubt about the library for the 32X, even with Sega's assurances that there would be a large number of games developed for the system. In early 1996, Sega conceded that it had promised too much out of the 32X and decided to stop producing the system in order to focus on the Saturn. Prices for the 32X dropped to $99 and cleared out of stores at $19.95.

Variations

More than a dozen licensed variations of the Sega Genesis/Mega Drive have been released. In addition to models made by Sega, alternate models were made by other companies, such as Majesco Entertainment, AtGames, JVC, Pioneer Corporation, Amstrad, and Aiwa. A number of bootleg clones were created during its lifespan.

First-party models

Genesis (second model)	Genesis CDX
Genesis Nomad	TeraDrive

In 1993, Sega introduced a smaller, lighter version of the console, known as the Mega Drive 2 in Japan, Europe, and AustraliaTemplate:Efn and simply sold as Genesis (without the Sega prefix) in North America. This version omits the headphone jack in the front, replaces the A/V-Out connector with a smaller version that supports stereo sound, and provides a simpler, less expensive mainboard that requires less power.

In April 1994, Sega released a combined, semi-portable Genesis/Sega CD unit called the Genesis CDX (marketed as the Multi-Mega in Europe). This unit retailed at $399.95 in the U.S. (roughly $100 more than the individual Genesis and Sega CD units put together, since the Sega CD dropped its price to $229 half a year before), and was bundled with Sonic CD, Sega Classics Arcade Collection, and the Sega CD version of Ecco the Dolphin. The CDX features a small LCD screen that, when the unit is used to play audio CDs, displays the current track being played. With this feature and the system's lightweight build (weighing two pounds), Sega marketed it in part as a portable CD player. While the Sega CD add-on received negative reviews, the CDX received most positive reviews, becoming the best-selling hybrid console of all time, due to requiring one power adapter.

In October 1995, Sega released a handheld version of the Genesis called the Genesis Nomad. Its design was based on the Mega Jet, a Mega Drive portable unit featured on airplane flights in Japan. As the only successor to the Game Gear, the Nomad operates on 6 AA batteries, displaying its graphics on a 3.25-inch (8.25-mm) LCD screen. The Nomad supports the entire Genesis library, but cannot be used with the Sega 32X, the Sega CD, or the Power Base Converter.

Exclusive to the Japanese market was the TeraDrive, a Mega Drive combined with an IBM PC compatible computer. Sega also produced three arcade system boards based on the Mega Drive: the System C-2, the MegaTech, and the MegaPlay, which support approximately 80 games combined.

Third-party models

Wondermega (JVC model)	Wondermega 2	Amstrad Mega PC
Genesis 3	Firecore	LaserActive

Working with Sega Enterprises, JVC released the Wondermega on April 1, 1992, in Japan. The system was later redesigned by JVC and released as the X'Eye in North America in September 1994. Designed by JVC to be a Genesis and Sega CD combination with high quality audio, the Wondermega's high price ($500 at launch) kept it out of the hands of average consumers. The same was true of the Pioneer LaserActive, which requires an add-on known as the Mega-LD pack, developed by Sega, in order to play Genesis and Sega CD games. Although the LaserActive was lined up to compete with the 3DO Interactive Multiplayer, the combined price of the system and the Mega-LD pack made it a prohibitively expensive option for Sega players. Aiwa released the CSD-GM1, a combination Genesis/Sega CD unit built into a boombox. Several companies added the Mega Drive to personal computers, mimicking the design of Sega's TeraDrive; these include the MSX models AX-330 and AX-990, distributed in Kuwait and Yemen, and the Amstrad Mega PC, distributed in Europe and Australia.

After the Genesis was discontinued, Majesco Entertainment released the Genesis 3 as a budget version in 1998. In 2009, AtGames began producing two new variations: the Firecore, which can play original Genesis cartridges as well as preloaded games, and a handheld console preloaded with 20 Genesis games. Companies such as Radica Games have released various compilations of Genesis and Mega Drive games in "plug-and-play" packages resembling the system's controller.

Re-releases and emulation

A number of Genesis and Mega Drive emulators have been produced, including GenEM, KGen, Genecyst, VGen, St0rm, and Gens. The GameTap subscription gaming service included a Sega Genesis emulator and had several dozen licensed Genesis games in its catalog. The Console Classix subscription gaming service includes an emulator and has several hundred Sega Genesis games in its catalog.

Compilations of Sega Genesis games have been released for other consoles. These include Sonic Mega Collection and Sonic Gems Collection for PS2, Xbox, and Nintendo GameCube; Sega Genesis Collection for PS2 and PSP, and Sonic's Ultimate Genesis Collection (known as the Sega Mega Drive Ultimate Collection in PAL territories) for PlayStation 3 and Xbox 360.

During his keynote speech at the 2006 Game Developers Conference, Nintendo president Satoru Iwata announced that Sega would make a number of Genesis/Mega Drive games available to download on the Wii's Virtual Console. There are select Sega Genesis games available on the Xbox 360 through Xbox Live Arcade, such as Sonic the Hedgehog and Sonic 2, as well as games available via the PlayStation Network and Steam.