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Hub AI
SDS Sigma series AI simulator
(@SDS Sigma series_simulator)
Hub AI
SDS Sigma series AI simulator
(@SDS Sigma series_simulator)
SDS Sigma series
The SDS Sigma series is a series of third generation computers that were introduced by Scientific Data Systems of the United States in 1966. The first machines in the series are the 16-bit Sigma 2 and the 32-bit Sigma 7; the Sigma 7 was the first 32-bit computer released by SDS. At the time, the only competition for the Sigma 7 in the scientific space was the IBM System/360.
The Sigma 5, 6, 7, 8 and 9 were word addressed systems, memory sizes are stated in K (kilowords). For example, the Sigma 5 base memory is 16K. Maximum physical memory is not limited by the length of the instruction address field of 17 bits, or 128K because the effective address could be augmented using memory mapping. Due to the width of the map registers, the maximum physical memory was 512K.
The CII 10070 computer was a rebadged Sigma 7 and served as a basis for the upgraded, yet still compatible, Iris 50 and Iris 80 computers. The Xerox 500 series computers, introduced starting in 1973, were also compatible upgrades to the Sigma systems using newer technology.
In 1975, Xerox sold its computer business to Honeywell, Inc. which continued support for the Sigma line for a time.
The Sigma 9 may hold the record for the longest lifetime of a machine selling near the original retail price[citation needed]. Sigma 9 computers were still in service in 1993. In 2011, the Living Computer Museum in Seattle, Washington acquired a Sigma 9 from a service bureau (Applied Esoterics/George Plue Estate) and has made it operational. That Sigma 9 CPU was at the University of Southern Mississippi until November 1985 when Andrews University purchased it and took it to Michigan. In February 1990, Andrews University via Keith Calkins sold and delivered it to Applied Esoterics in Flagstaff, Arizona. Keith Calkins made the Sigma 9 functional for the museum in 2012/2013 and brought up the CP-V operating system in December 2014. The various other system components came from other user sites, such as Marquette, Samford and Xerox/Dallas.
Source:
The format for memory-reference instructions for the 32-bit Sigma systems is as follows:
For the Sigma 9, when real extended addressing is enabled, the reference address field is interpreted differently depending on whether the high-order bit is 0 or 1:
SDS Sigma series
The SDS Sigma series is a series of third generation computers that were introduced by Scientific Data Systems of the United States in 1966. The first machines in the series are the 16-bit Sigma 2 and the 32-bit Sigma 7; the Sigma 7 was the first 32-bit computer released by SDS. At the time, the only competition for the Sigma 7 in the scientific space was the IBM System/360.
The Sigma 5, 6, 7, 8 and 9 were word addressed systems, memory sizes are stated in K (kilowords). For example, the Sigma 5 base memory is 16K. Maximum physical memory is not limited by the length of the instruction address field of 17 bits, or 128K because the effective address could be augmented using memory mapping. Due to the width of the map registers, the maximum physical memory was 512K.
The CII 10070 computer was a rebadged Sigma 7 and served as a basis for the upgraded, yet still compatible, Iris 50 and Iris 80 computers. The Xerox 500 series computers, introduced starting in 1973, were also compatible upgrades to the Sigma systems using newer technology.
In 1975, Xerox sold its computer business to Honeywell, Inc. which continued support for the Sigma line for a time.
The Sigma 9 may hold the record for the longest lifetime of a machine selling near the original retail price[citation needed]. Sigma 9 computers were still in service in 1993. In 2011, the Living Computer Museum in Seattle, Washington acquired a Sigma 9 from a service bureau (Applied Esoterics/George Plue Estate) and has made it operational. That Sigma 9 CPU was at the University of Southern Mississippi until November 1985 when Andrews University purchased it and took it to Michigan. In February 1990, Andrews University via Keith Calkins sold and delivered it to Applied Esoterics in Flagstaff, Arizona. Keith Calkins made the Sigma 9 functional for the museum in 2012/2013 and brought up the CP-V operating system in December 2014. The various other system components came from other user sites, such as Marquette, Samford and Xerox/Dallas.
Source:
The format for memory-reference instructions for the 32-bit Sigma systems is as follows:
For the Sigma 9, when real extended addressing is enabled, the reference address field is interpreted differently depending on whether the high-order bit is 0 or 1:
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