GE-200 series
The GE-200 series was a family of small mainframe computers of the 1960s, built by General Electric. GE marketing called the line Compatibles/200. The GE-210 of 1960 was not compatible with the rest of the 200 series.
200 series models
The main machine in the line was the GE-225. It used a 20-bit word, of which 13 bits could be used for an address. Along with the basic central processing unit the system could also have had a floating-point unit, or a fixed-point decimal option with three six-bit decimal digits per word. It had eleven I/O channel 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 used magnetic-core memory, and a standard 8 kiloword system held 186,000 magnetic cores. They weighed about.The GE-215 was a scaled-down version of the GE-225, including only six I/O channels and only 4 kilowords or 8 kilowords of core.
The GE-205.
The GE-235 was a re-implementation of the GE-225 with three times faster memory than the original. The GE-235 consisted of several major components and options:
- Central processor
- 400 card-per-minute or 1000 CPM card reader
- 100 CPM card punch or 300 CPM card punch
- Perforated tape subsystem
- Magnetic tape subsystem
- 12-pocket high-speed document handler
- On-line high-speed printer or off/on-line speed printer
- Disc storage unit
- Auxiliary Arithmetic Logic Unit
- DATANET data communications equipment
Background
DTSS
Through the early 1960s GE worked with Dartmouth College on the development of a time-sharing operating system, which would later go on to become the Dartmouth Time-Sharing System. The system was constructed by attaching a number of teletypewriters to a smaller GE machine called the DATANET-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 in batch mode, and the illusion of multitasking was being maintained externally.
In 1965 GE started packaging the DN-30 and GE-235 systems together as the GE-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 the BASIC programming language was created.