GE-200 series
The GE-200 series wasfamilysmall mainframe computers of1960s, built by General Electric.The main machine inline wasGE-225. It used20-bit word,which 13 bits could be usedan address. Along withbasic CPUsystem could also includefloating point unit, or interestingly,fixed point decimal optionthree 6-bit decimals per word. It had 11 I/O channel controllers,GE soldvarietyadd-ons including disks, printersother devices. The machines were built using discrete transistors, withtypical machine including about 10,000 transistors20,000 diodes. They used core memory, andstandard 8k-word system held 186,000 magnetic cores.
The GE-215 wasscaled-down version ofGE-225, including only 6 I/O channelsonly 4K or 8Kcore. The GE-235 wasre-implementation ofGE-225 withfaster memory which ran three times faster thanoriginal.
Throughearly 1960s GE workedDartmouth College ondevelopment oftime-sharing operating system, which would later go onbecome DTSS. The system was constructed by attachingnumberteletypewriters tosmaller GE machine calledDatanet-30, which wassmall computer that had evolved fromearlier process-control machine.
DTSS was an odd system,didn't run onGE-235, butDN-30 instead. The DN-30 accepted commands one attime fromterminals connectedit,then ran their requested programs onGE-235. The GE-235 had no ideawas not runningbatch mode, andillusionmultitasking was being maintained externally. This represents an interesting stage inevolutionmultitasking.
In 1965 GE started packagingDN-30GE-235 systems together asGE-265. The GE-265 achieved fame not onlybeingfirst time-sharing system, butwas alsomachine on whichBASIC programming language was first created.
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