Varian Data Machines

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For other uses of "Varian", see Varian (disambiguation).

Varian Data Machines was a division of Varian Associates which sold minicomputers. It entered the market in 1966,[1] but met stiff competition and was bought by Sperry Corporation in 1977.[2]

The 620i and 620/L series were parallel, binary 16-bit general-purpose digital computers with core memory expandable to 32,768 words. An 18-bit word length was optionally available. A basic machine cycle took 1.8 microseconds, and the core memory read time was 700 nanoseconds. The computers uses two's complement arithmetic and had four main registers - accumulator A, accumulator extension B, an index register X and a program counter register. Addressing modes were direct, immediate and indexed. The instruction set had more than one hundred artihmetic, logic and control instructions and supported microprogramming. These models used a hardware front panel console that allowed starting and stopping the machine, examining memory and registers and changing memory or registers with front-panel switches. The processor was made with integrated circuit transistor transistor logic from the 7400 series. The system was packaged in a 19 inch rack and used 340 watts of power at 120 V AC. The 620/F was a variation with a faster machine cycle time of 750 nanoseconds. The 620/L 100 was released in 1973. It had a cycle time of 950 nanoseconds and a more compact system chassis than the 620/F. [3] The 70 series had semiconductor memory but also supported core. Various models were released between 1972 and 1977. [4]


  1. ^ HP: The Accidentally, On-Purpose Computer Company
  2. ^ Computer History Museum, Selling the Computer Revolution - Marketing Brochures in the Collection: Varian Data Machines
  3. ^ Varian 620 Manual retrieved 2012 July 24
  4. ^ MInicomputer Orphanage, retrieved 2012 July 24