CDC Cyber

The Cyber range of mainframe computers were Control Data Corporation's primary products during the 1970's and 1980's. The Cyber line included three very different models of computer, the 170 series based on the architecture of the CDC 6600 and CDC 7600, the 180 series developed by a team in Canada, and the 200 series based on the CDC STAR-100. Primarily aimed at large office applications instead of the traditional supercomputer tasks, some of the Cyber machines nevertheless included basic vector instructions for added performance in "traditional" CDC roles.

CDC Cyber 170 series

Like the earlier 6600/7600, the Cyber 170 design was based on a 60-bit word, storing up to 10 6-bit characters, and used the same instruction set. The Central Processor (CU) was a basic CPU that ran at either 25 or 40MHz, and was equipped with 10, 15 or 20 Peripheral Processors (PP), high-performance channel controllers for high-speed I/O. The CPU was normally equipped with a small amount of high-speed cache memory, typically 2k words, and eight addressing, eight instruction and eight index registers.

The Peripheral Processors used a technique known as Barrel and Slot to share the execution unit; each processor had its own memory and registers, but the CPU (the Slot) itself executed one instruction from each processor in turn (the Barrel). This is a crude form of hardware multiprogramming. The PP's were considerably simpler than those used on earlier machines, which were full computers, relying on the CU to handle code and thereby lowing the cost of the PP's, and the machine as a whole.

Cyber systems normally included either 256k or 512k-words of memory. They were originally equipped with core memory, but the falling prices and improving perfomance of semiconductor-based memory allowed them to move off of core in the late 1970s.

The systems typically ran CDC's NOS (Network Operating System), 1.4 or 2.0. Several other operating systems were available for the machine, but the only one to see any real use on the 170's was NOS/BE, providing time sharing for batch and interactive applications.

CDC Cyber 180 series

As the entire computing world moved to byte-oriented machines, CDC customers started pushing for th Cyber machines to do the same. The result was a new series of 170s that could operate in either 60-bit or 64-bit modes, although not at the same time.

During the lifetime of the 170 series CDC introduced NOS/VE, which added virtual memory to the BE system. They considered this change so important that the newer machines able to run VE were referred to as the Cyber 180 after its release. The machines were otherwise identical to the bytewise 170s.

CDC Cyber 200 series

In 1974 CDC introduced their STAR architechture, itself a version of the 6600/7600 design with vector processing instructions added for high performance on math tasks. The original STAR proved to be a great disappointment when it was released, but many of its problems seemed solvable.

In the late 1970s CDC finally addressed these issues and re-entered the supercomputer market with the Cyber 203, the new naming in keeping with their new branding, and perhaps to distance itself from the STAR's failure. An improved version was later released as the Cyber 205, and sold fairly well. Versions were available with one to four vector pipelines, the 4-pipe version theoretically delivering 200 MFLOP in later versions, but rarely coming close on anything other than hand-written assembly language.