Twins – The story of Sega's first console

Sega was living large as one of the United States top arcade game manufacturers of the early 1980’s with hits such as Zaxxon. Despite their successes, 1982 saw the arcade market experience an economic downturn. With their arcade business in decline, Sega decided to use their hardware expertise to move into the home consumer market in Japan. What would come from this decision would go on to shape the entire video game industry as we know it. While their future console endeavors would prove to be more successful, Sega would enter the home console market with a set of twins.

Prior to release

When it came time to create their first piece of hardware for the home, Sega chose to use popular off the shelf components that would keep costs down and ensure longevity. Of note was the popular Zilog Z80 8-bit microprocessor. Sega had been using the Z80 processor in their recent arcade titles and using it again would ensure easier porting of their catalog of arcade titles.

Work progressed on Sega’s new hardware as they created a computer with a built-in keyboard that would come to be known as the SC-3000. While development of the SC-3000 was ongoing, Sega learned of arcade competitor Nintendo’s plans to also enter the Japanese consumer market. Nintendo was working on a games-only console, known as the Famicom. Armed with this knowledge Sega was faced with some tough decisions. Sega knew their computer wouldn’t be able to compete with the Famicom head on price wise. Instead of scrapping their work up until that point, Sega opted to also create a games-only console of their own. One that would use hardware similar to the SC-3000, but act as a cost reduced version. This new piece of hardware would come to be known as the SG-1000.


June 15th, 1983 would see Sega enter the home console market alongside competitor Nintendo. Despite competition from the technically superior Nintendo Famicom, Sega’s SG-1000 did quite well. Sega had predicted the SG-1000 would go on to sell 50,000 units in its first year, but were surprised when they ended up selling 160,000 globally. The SG-1000 was released at a price point of ¥15,000, and with 3 launch titles. With Sega’s backlog of arcade titles and licensing deals, the SG-1000 would go on to amass a library of 21 games by the end of 1983.

Released alongside the SG-1000 was its twin, the SC-3000. Coming in at a price point of ¥29,800, the SC-3000 had the benefit of using the same game cartridges as the SG-1000, thus sharing the same game library. In addition to games, the SC-3000 also had access to BASIC cartridges for writing your own programs and saving them to the cassette tape with Sega’s data recorder SR-1000. Afraid that the SC-3000 wasn’t seen as a worthwhile business computer due to its membrane keyboard, Sega would go on to release the enhanced fully mechanical SC-3000H later in the year for ¥33,800. While the SG-1000’s main competition came from the Nintendo Famicom, the SC-3000 competed directly with the MSX line of computers. The SC-3000 had the benefit of offering similar hardware to the MSX at a cheaper price point. Despite the pricing difference, Sega could not compete with the vast amount of software available to the MSX line and in its first year would go on to sell 120,000 units globally.

Sega’s strategy for these systems was much different to their competitors. While Nintendo and the MSX embraced 3rd party support, Sega chose to make all of their software themselves. Sega saw no reason to embrace 3rd parties that they only saw as competition. This choice would go on to heavily hurt Sega for years to come.


While the SC-3000 and SG-1000 were a success for Sega, it was obvious that they were significantly behind the competition. In the time the SG-1000 had sold around 160,000 units, the Nintendo Famicom had sold around 500,000 globally. Thus on July 31 1984, Sega would release the confusingly named SG-1000 II for ¥15,000. While the internals remained the same, the system was enhanced with 2 controller ports, instead of an attached joystick and new controllers more in line with that of the Famicom. Sega also released the SK-1100 keyboard attachment for the SG-1000 II so that it could utilize some of the software exclusive to the SC-3000 and 3000H. On the SC-3000 side, Sega released the Super Control Station SF-7000, a 3-inch floppy disk drive that added 64kB of RAM, 8kB of ROM, a Centronics parallel port and an RS-232 serial port that came in at a whopping ¥79,800.

1985 – The end of the road

Sega would go on to create a new medium for games called Sega My Cards, which were cheaper and smaller than game cartridges as they typically used smaller ROM’s. These card shaped games required the use of the Sega Card Catcher. The Sega Card Catcher was designed for the SG-1000 and SG-1000 II, but would come built in on Sega’s new system in the works.

Sega realized that the gap in power between the SG-1000 and the Nintendo Famicom would only continue to grow. Nintendo implemented enhancement chips on the cartridges of Famicom games that gave the console even greater power over the competition. While a great strategy, Sega knew enhancement chips would only drive up the costs of video game cartridges for consumers and opted to take another approach. Sega began work on a successor to the SG-1000. Rather than put enhancement chips into cartridges, Sega would create a whole new console, more powerful than the last and backwards compatible with older SG-1000 titles. This console would come to be known as the Mark III.

Sales figures after 1983 for the SC-3000 line of computers are near impossible to find, but it’s believed the computers didn’t have significant sales after the first year. Either way, Sega saw that their future was in game consoles and not computers. Unlike the SG-1000, there would be no successor for the SC-3000. While the SG-1000 and the SC-3000 entered the market as twins, The SG-1000 would evolve into an only child.


Many people see the SG-1000 as a failure, but that’s not a fair statement to make. The SG-1000 would exceed Sega’s sales expectations and be the beginning of a console family that would go on to dominate in the 80’s and 90’s. The SG-1000 would be discontinued in 1985 to make way for the Mark III, selling an estimated 1.4 million units globally. Amassing a library of 79 games and 26 educational and programming cartridges with the use of the SK-1100 keyboard, the SG-1000 would go on to see its last commercial release in 1987.

While not as critically acclaimed or commercially successful as the Famicom, the SG-1000 and SC-3000 continue to see love with homebrew releases to this day and holds the title of being Sega’s foray into the home consumer market.

#RetroGaming #Sega #SG1000 #SC3000 #Famicom #8bit