History of video games/Platforms/Sega Genesis

Development
The system was preceded by the Sega Master System.

Sega approached Atari about bringing the MegaDrive to the American market. After negotiations broke down Sega decided to launch the console in the United States on their own.

Following development of the base console a number of add on devices were developed. Development of the Sega CD was particularly problematic, with drive motors occasionally catching on fire in pre production units.

Japan
In October of 1988 the Sega Mega Drive was released in Japan at a cost of 21,000 yen.

On May 31st, 1991 the TerraDrive computer and Mega Drive hybrid system was released in Japan.

North America
The Sega Genesis was launched in North America in 1989. Notably, future president of the United States Donald Trump attended the 1989 Genesis launch in Manhattan.

The Genesis did very well in North American gaming market. This is especially impressive, as at launch time rival Nintendo held over 80% of the market for home video games in the United States of America, and by 1990 would control over 90% of the American game market. By launching quality first party exclusive games, courting unique third party developers with fewer artistic restrictions, listening to consumer feedback, and launching aggressive marketing campaigns, Sega was able to take on an entrenched industry titan and become one itself by briefly taking over half of the market for itself, An event widely considered to be one of the gaming industry's most important upsets.

Worldwide
The Mega Drive saw a European release in 1990.

Refresh
To make the platform more competitive, Sega would release two major add ons to expand the system's capabilities. The Sega CD was released in 1992, and gave the system a CD drive with massively improved storage capacity as a result. The Sega 32x was released in November 1994 for $160, and massively increased the system's raw power, though not nearly enough to be competitive with the new consoles it was meant to fend off. Both add ons would have exclusive games that could not be played on a standard Genesis or Mega Drive.

Legacy
The Genesis influenced a number of contemporary systems. The Sega Genesis was directly followed by the ill fated Sega Saturn. A portable Genesis was also made as the Nomad. A Mega Drive module was also produced for the Pioneer LaserActive.

The Sega Genesis was discontinued in 1997 outside of Brazil. However the console continued to be a popular choice in certain markets after this date. Sega partner Tectoy was still selling 150,000 consoles annually as of 2016. In 2016 Tectoy began taking preorders for a 2017 revision of the console for the Brazilian market at a cost of 399 Brazilian real. In 2010 Mega Drive gaming was still popular in Egypt. 29 million Sega Genesis consoles were sold.

Compute
The Genesis is powered by a primary 16-bit Motorola 68000 processor clocked at 7.6 megahertz. A secondary 8-bit Z80 coprocessor was clocked at 3.5 megahertz.

The Genesis has 64 kilobytes of RAM dedicated to the primary processor, and 8 kilobytes dedicated to the Z80 coprocessor.

Some games used cartridge based chips to allow for 3D graphics.

The Sega Genesis was initially considered easier for developers to use then the competing SNES due to it's straightforward design instead of reliance on support hardware.

Graphics
The Genesis uses a custom chip called the Video Display Processor (VDP) clocked at 13 megahertz for rendering graphics. The VDP has 64 kilobytes of RAM, 128 bytes of color RAM, and 80 bytes of vertical scroll RAM. The Genesis could render 80 sprites and 64 simultaneous colors from 512 total colors.

Blast Processing was technically a feature supported by the Genesis VDP, though it was simply a technique used to generate images with more colors and was never widely used on official Genesis games.

Storage
Genesis cartridges typically maxed out at 4 megabytes, though a few 5 megabyte cartridges exist.

Cartridges were region locked through a combination of software and hardware methods, with mixed results and variations on usage while the console was on the market.

Networking
The Sega Channel was an expensive service that allowed games to be temporarily downloaded over a cable connection.

The third party X-Band service allowed some games to be played online.

Sonic the Hedgehog
The flagship fast paced mascot platformer and system seller for the console.

Read more about Sonic the Hedgehog on Wikipedia.

Zero Wing
Originally released as an arcade game in 1989.

The Japanese version of Zero Wing had 35 different endings, a notable feat for the time.

The poor English translation of Zero Wing sparked the early 2000's internet meme "All your base are belong to us".

Read more about Zero Wing and All your base are belong to us on Wikipedia.

Art Alive!
An early art program for the console.

Read more about Art Alive! on Wikipedia.

1992

 * Sonic the Hedgehog 2

Ecco the Dolphin
Game creator Ed Annunziata was a prolific reader of the works of scientist John C. Lilly, who closely studied dolphins. Annunziata is also said to have been influenced by the work of musician Pink Floyd.

Read more about the original Ecco the Dolphin game on Wikipedia.

1993

 * Disney's Aladdin
 * NBA Jam
 * Mortal Kombat II - Retained the gore effects from the Arcade version.

Sonic CD
The intro movie to Sonic CD is considered by many to be iconic.

Read more about Sonic CD on Wikipedia.

1994

 * Sonic the Hedgehog 3
 * Sonic & Knuckles

Wacky Worlds
An indirect successor to Art Alive!. It featured Sonic the Hedgehog and competed against Nintendo's Mario Paint.

CrazyBus
An infamous homebrew title.

Special edition consoles

 * HeartBeat Personal Trainer- A rare North America variant of the Sega Genesis equipped with motion sensors. Just 1,000 versions of this were produced, with a small number of accompanying exclusive games reliant on motion controls.
 * CSD-GM1 - CD Player with integrated Mega Drive.

Development
There is a WikiBook on Genesis Programming.