TheGE-200 series was a family of smallmainframecomputers of the 1960s, built byGeneral Electric (GE). GE marketing called the lineCompatibles/200[1] (GE-205/215/225/235).[2] The GE-210 of 1960[3] was not compatible with the rest of the 200 series.[4]
The main machine in the line was theGE-225 (1961).[5][3] It used a 20-bitword, of which 13bits could be used for anaddress. Along with the basiccentral processing unit (CPU) the system could also have had afloating-point unit (the "Auxiliary Arithmetic Unit"), or afixed-point decimal option with three six-bit decimal digits per word. It had elevenI/Ochannel controllers, and GE sold a variety of add-ons including disks, printers, and other devices. The machines were built using discrete transistors, with a typical machine containing about 10,000 transistors and 20,000 diodes. They usedmagnetic-core memory, and a standard 8 kiloword system held 186,000 magnetic cores. They weighed about 2,000 pounds (1.0 short ton; 910 kg).[6][7]
TheGE-215 (1963)[3][8] was a scaled-down version of the GE-225, including only six I/O channels and only 4 kilowords or 8 kilowords of core.
TheGE-205 (1964).[2]
TheGE-235 (1964)[3] was a re-implementation of the GE-225 with three times faster memory than the original.[9] The GE-235 consisted of several major components and options:
The series was designed by a team led byHomer R. “Barney” Oldfield, and which includedArnold Spielberg (father of film directorSteven Spielberg). GE chairmanRalph J. Cordiner had forbidden GE from entering the general purpose computer business, rejecting several proposals by Oldfield by simply writing "No" across them and sending them back. Oldfield, somewhat deceptively, claimed that the GE-200 series would be industrial control computers. By the time Cordiner found out otherwise, it was too late and the machine was in production; Cordiner fired Oldfield at the product rollout. Even though the machine was selling well, Cordiner ordered that GE leave the computer business within 18 months (it actually took several years).[10][11]
Through the early 1960s GE worked withDartmouth College on the development of atime-sharingoperating system, which would later go on to become theDartmouth Time-Sharing System (DTSS). The system was constructed by attaching a number ofteletypewriters to a smaller GE machine called theDATANET-30 (DN-30), which was a small computer that had evolved from an earlier process-control machine.
DTSS actually ran on the DN-30. The DN-30 accepted commands one at a time from the terminals connected to it, and then ran their requested programs on the GE-235. The GE-235 had no idea it was not running inbatch mode, and the illusion ofmultitasking was being maintained externally.
In 1965 GE started packaging the DN-30 and GE-235 systems together as theGE-265. The GE-265 achieved fame not only for being the first commercially successful time-sharing system, but it was also the machine on which theBASIC programming language was created.
{{cite web}}: CS1 maint: others (link)Central Processor and Control Console (with 4K or 8K memory, typewriter, and card reader)
As a computer designer and engineer, Arnold worked on and helped design the groundbreaking GE-225 mainframe computer in 1960, which would go on to form the basis for the coding tools that would pave the way for personal computing.