A logic package of NEAC Series 2200 Model 700

A logic package of NEAC Series 2200 Model700

A logic package of NEAC Series 2200 Model700



NEAC Series 2200 Model 700 System (from the 10th anniversary issue of Tohoku university large scale computer center report)

NEAC Series 2200 Model 700 System (from the 10th anniversary issue of Tohoku university large scale computer center report)



NEAC Series 2200 Model 700 System (from the 10th anniversary issue of Tohoku university large scale computer center report)

NEAC Series 2200 Model 700 System (from the 10th anniversary issue of Tohoku university large scale computer center report)



Manufactured in 1968
Manufactured by NEC Corporation
Owner NEC Corporation
Location of historical materials NEC Corporation
1-10, Nisshin-cho, Fuchu, Tokyo, 183-8501, Japan
Visitor information Not open to the public (Ask for a visit)
Contact Platform Planning Division, NEC Corporation Tel.+81-44-435-5433


The NEAC Series 2200 Model 700 was the large-scale computer announced in November 1968. This model 700 was developed by NEC own technology and was the highest model in this series. The feature are described as below.

  • NEC delivered the previous model (model 500) to Osaka University as the MAC system and realized time-sharing system which enables many users, located at various terminals, to make and execute programs interactively for the first time in Japan. Based on that experience, the model 700 achieved a larger and faster time-sharing system.

  • A fixed-point arithmetic cycle time achieved 0.5 micro seconds and a floating point arithmetic cycle time achieved 0.8 micro seconds by using the high-speed CML ICs. 0.5 micro seconds cycle time and maximum 2 million characters could be supported as the main memory. In addition, cache memory were also applied. At that time, model 700 was the largest and fastest system in Japanese computer vendors.

  • Regarding Operating System, NEC developed the enhanced operating system MOD7 to achieve best system performance with tightly coupled multi-processor.

  • In order to enable a card test, NEC implemented scan path circuit inside a flip flop IC for the first time in the world. This technique also enabled system diagnostic test data to build automatically. Thus NEC applied state-of-the-art technology for model 700 to improve testability and reliability.

  • For outer memory unit, the grouped magnetic disk unit was configured by equipping disk packs with 16 spindles, and thus memory capacity was 294 million characters.