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Sega Mark III

The 8 Bit Sega machines have a slightly complicated history, due to the rapidly changing arcade market requiring their home versions to become more sophisticated in a short space of time, but also the company having to compete with Nintendo and their hard business policies toward third party developers, who were effectively barred from making games on rival consoles.

The Sega Mark III was released in October 1985. It was a major update of the original SG-1000 and Mark II hardware, with a few new features.

It is the first Sega console to have a composite video socket, and also had slots either side of the machine for the two controllers. The expansion slot on the rear was used for peripherals such as the FM sound unit.

The console had it's own library of games, which came in gold coloured boxes, there were updated games from the earlier consoles, as well as original titles, and conversions of Sega's newer arcade machines, The Mark III is also fully compatible with all SG-1000 software, although the video hardware changes the colours on screen somewhat.

The first two marks could use the Sega MyCard, which were small, credit card sized carts that an adaptor called the Card Catcher was needed for the first two models. The Mark III had the card slot built in the front of the console, as well as the normal cartridge slot on top of the machine.

Soundwise, the console has not changed much, but an FM sound module could be added for games that used this advanced capability. This module was built into the next machine, the Master System as standard. 

The machine was not a great success at retail, and was replaced by the Master System after about 18 months, in Japan, this was also not a success, but after 1986, Sega were wise not to chase markets where Nintendo were dominant, such as Japan and the US, and went to Europe and South America, where finally great success would be had, firstly with the Master System, then the Megadrive.

The Mark III was the stepping stone technically for Sega to have this domination in Europe and the emerging games markets such as Brazil, the latter's games market would be dominated by their partner Tec Toy for the best part of three decades.

Our machine was very kindly donated by Johnny Blanchard.


Manufacturer: Sega
Date: 1985

Other Systems Related To Sega Mark III:

Item Manufacturer Date
Sega SC-3000 Sega 1983

This exhibit has a reference ID of CH60600. Please quote this reference ID in any communication with the Centre for Computing History.

Sega Mark III

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