AN/USQ-17
| Industry | Computer hardware, Military electronics |
|---|---|
| Predecessor | Sperry Rand (as original developer) |
| Founder | Seymour Cray (designer) |
| Products | AN/USQ-17 (Naval Tactical Data System computer), UNIVAC 490, UNIVAC 494 |
The AN/USQ-17, commonly identified as the Naval Tactical Data System (NTDS) computer and labeled in Sperry Rand documentation as the Univac M-460, represents the last design developed by Seymour Cray for UNIVAC. This model was later commercialized by UNIVAC under the name UNIVAC 490, which eventually evolved into a multiprocessor variant known as the 494.
Within the framework of the Joint Electronics Type Designation System (JETDS), the designation "AN/USQ-17" signifies the 17th piece of Army-Navy electronic equipment classified as general utility special combination gear. JETDS currently governs the naming conventions for all electronic devices used by the Department of Defense.
Overview
The initial version of this computer occupied a space roughly equivalent to a refrigerator, standing around four feet (1.20 m) tall, featuring a hinged top for component access. Shortly after completing this prototype, Cray departed to join Control Data Corporation. Following a US$50 million contract awarded by the Navy to Sperry Rand for producing the AN/USQ-17, engineers at Univac completely redesigned the system using silicon transistors while preserving the original instruction set to ensure compatibility with existing software.
To enhance accessibility, the updated model was configured to stand upright, resembling a double-door refrigerator approximately six feet (1.80 m) in height, and was renamed as the AN/USQ-20.
The instruction words were 30 bits in length and divided into fields including a 6-bit function code, 3-bit jump condition, 3-bit partial word specifier, 3-bit index register selector, and a 15-bit operand address.
Data words measured 30 bits, enabling storage of five alphanumeric characters encoded with 6 bits each. The main memory comprised 32,768 words (32K) of core memory.
The processor's registers consisted of:
- A single 30-bit accumulator (A)
- A 30-bit Q register that combined with A to produce 60-bit results for multiplication and division
- Seven 15-bit index registers labeled B1 through B7
The instruction format implemented in the AN/USQ-17 established a foundation for an instruction set architecture that continued to develop in subsequent UNIVAC systems, including the still-functioning UNIVAC 1100/2200 series.
- AN/USQ-17, 30-bit architecture, March 1958
- CP-642, also known as AN/USQ-20, 30-bit, introduced in 1960
- AN/UYK-8, 30-bit system from 1967
- AN/UYK-7, featuring 32-bit processing, released in 1971
- AN/UYK-43, a 32-bit model launched in 1984
- AN/UYK-20, employing a 16-bit design from 1973
- AN/AYK-14, another 16-bit device introduced in 1980
- AN/UYK-44, a further 16-bit system deployed in 1984
See also
- List of military electronics of the United States
- List of UNIVAC products
- History of computing hardware
External links
- “M-460 Computer Characteristics” – PDF document, 32 pages (1956)
- The Univac M-460 Computer – Technical paper authored by J. E. Thornton, M. Macaulay, and D. H. Toth from Remington Rand Univac Division of Sperry Rand (available online at Ed Thelen's Antique Computer Home Page)