RCA Spectra 70
The RCA Spectra 70 is a line of electronic data processing (EDP) equipment that was manufactured by the Radio Corporation of America’s computer division beginning in April 1965.Competition in the mainframe market was fierce, and in 1971 the company sold the computer division and the Spectra 70 line to Sperry Rand, taking a huge write down in the process.TSOS was the first mainframe, demand paged, virtual memory operating system on the market.Memory limitations and relatively low processing speed made its use as a stand-alone computer system somewhat impractical.It implemented a small subset of 25 instructions of the full Spectra 70 architecture,[3]: p.10 and was not downward compatible with the rest of the range.The 70/15 was often used as a satellite processor for larger systems or used as an intelligent terminal for remote job entry.Typical applications of a satellite processor would include card-to-tape conversion, card/tape-to-printer report generation, tape-to-card punching, input pre-processing and verification, or tab-shop tasks like file sorting, merge, and data selection.Like the Model 15, it implemented a (slightly larger) subset of 31 instructions of the full range architecture.[9][10] It was a medium-scale computer combining third-generation technology (including integrated circuits)[7] and speed in an efficient low-cost data system.A floating-point processor was available as an option and the 70/45 was considered suitable for commercial, scientific, communications, and real-time applications.The memory cycle time was 1.44 microseconds to access two bytes (one half word) of information.Although these computers were fast and reliable they came too late to impact the lead of the IBM 360 product line.
electronic data processingRadio Corporation of Americainstruction setIBM System/360EBCDICoperating systemmainframeSperry Randwrite downupward-compatiblemicrosecondsExtended Binary Coded Decimal Interchange Codemultiplexerfloating-pointdecimalbinaryfixed-point arithmeticvirtual memoryTime Sharing Operating Systemdemand pagedIBM System/370English Electric System 4English ElectricprocessorapplicationscomputerIBM System/360 Model 20terminalcard-to-tape conversioncard punchingsortingInput-Output ControlUtility RoutinesReport Program Generatormulti-processorthroughputbatch processingintegrated circuitsthird-generation computerstimesharinginstruction set architectureprintersmagnetic tapeDirect access storageaccess timemillisecondsdisc-packkbyte/sMass Storageoptical character recognitionscannerHistory of computing hardware (1960s–present)UNIVAC Series 70