This history describes Fujitsu’s operating systems for office computers until the year 2000.
Fujitsu’s office computers stem from two origins. The first stream started with the FACOM 230-10, and the other started with the USAC series, which was originated by Unoke Electronic Industries (the company name was changed to USAC Electronic Industrial in 1969 and later to PFU). A three-company group, consisting of Fujitsu and USAC, together with Uchida Yoko, developed these two streams into one large stream. The operating systems for the group’s office computers also evolved while being influenced by these two streams.
1.The dawn of office computers (1960s and 1970s)
The oldest machines in the group’s office computer history are the USAC 5010 and USAC 3010, which Unoke Electronic Industries completed in 1961. The concept of an operating system did not exist at this time. The USAC series was distinctive for being designed specifically as billing machines, and, in 1971, the USAC 720 series was rolled out with a common architecture for the entire series. This series was provided with characteristic functions and concepts, such as a simplified programming language for billing processes, that would be used in the group’s later office computers.
At the same time, Fujitsu was covering the office computer field with the FACOM 230-10, which was distinctive for being a small general-purpose computer, and later the FACOM 230-15. Fujitsu also gradually developed the basic software that allowed these machines to be used as general-purpose computers. With the FACOM 230-15, which was announced in April 1970, Fujitsu provided SPIRAL, the first true Fujitsu small-computer operating system with a name. SPIRAL offered a paging function that was revolutionary for a small computer.
2.The FACOM V series, Bm, and System 80 era (mid-1970s to mid-1980s)
Fujitsu, USAC Electronic Industrial, and Uchida Yoko began working as a group with the development of the FACOM V series, which started with the FACOM V0, announced in August 1974. The group developed UNIOS as the operating system for the FACOM V series. The UNIOS name itself, standing for “unique and universal operating system,” gives a sense of the companies’ enthusiasm about the operating system. Three UNIOS versions — UNIOS/F1, UNIOS/F2, and UNIOS/F4 — were created for different machine sizes and applications in order to cover as wide a range as possible. By offering different versions of one operating system, the group was striving for operating system consistency based on a common concept, although complete integration was still a few years away. The 4D concept below was the factor that unified the operating systems. True integration, however, would have to wait for the CSP (CSP/FX) operating system on the FACOM K series.
- （1）Data communications (DC) — flexible creation of network systems through UNIOS
- （2）Databases (DB) — provide user-friendly database functions for central data management
- （3）Data entry (DE) — provide functions for easy data creation and input at the sites of office tasks
- （4）Data utilities (DU) — provide development functions and tools to simplify computer use
In parallel with the FACOM V series, the group moved ahead with the development of the FACOM Bm (announced in December 1977 and identical to the USAC 820), followed by the FACOM System 80 series (announced in April 1979) to cover the ultra-small machine market, including billing-machine-like applications, that the FACOM V series could not cover. These new office computers provided functions, called Direct Data Processing Systems (DDPS), to meet on-site data processing needs. These functions became part of the large trend at the end of the 1970s toward end users engaging in processes interactively using a display terminal. The group made the BMOS operating system for the FACOM Bm and the CPS80 operating system for the FACOM System 80 series. These operating systems had
- Billing computers
- Branch computers
- Terminal computers
Examples of functions that supported DDPS needs included the simplified BOL-1 programming language, the SIMPL pattern-based software package, and the multi-workstation functions provided by CPS80.
3.The FACOM K series and later era (mid-1980s onward)
As described above, UNIOS was specialized for large machines, and BMOS and CPS80 were specialized for small machines and on-site operations. Over time, however, it became necessary to integrate these two operating systems. The operating system that finally emerged to do this was called CSP, which first appeared on the FACOM K series announced in May 1984. Initially, CSP consisted of three versions — CSP/F1, CSP/F3, and CSP/F5 — which were designed for compatibility with previous machines and application specialization while maintaining consistency among all K series operating systems. Later, CSP/F3 and CSP/F5 were merged into CSP/FX, which was superseded by ASP, the operating system for the series that followed the FACOM K series (the FUJITSU K6000 series and the GRANPOWER 6000 series).
CSP/F1, which was installed on the FACOM K-10/10R, the most typical model of the FACOM K series, supported on-site operation, distributed processing, and scalability and offered enhanced open-system support so that it could coexist with UNIX workstations and personal computers. Eventually, however, office computers were forced to concede their role to personal computers.