View source for Engineering:GE-400 series

{{more references|date=June 2017}}
{{Infobox CPU architecture
| name       = GE 400
| designer   = [[Company:General Electric|General Electric]]
| bits       = 24-bit
| introduced = 1964
| design     = CISC
| type       = Register-Memory<br>Memory-Memory
| encoding   = Fixed
| branching  = Condition indicators<br>Compare and branch
| endianness = 
| extensions = 
| open       =
| registers  = Accumulator<br>6 index registers (in memory) 
| gpr = none
| fpr = none
}}
The '''GE-400 series''' were [[Time-sharing|time-sharing]] Information Systems computers by [[Company:General Electric|General Electric]] introduced in 1964 and shipped until 1968.

==System description==
The GE-400 series (Compatibles/400) came in models: 415, 425, 435 (1964),<ref>{{Cite book|url=https://books.google.com/books?id=REWeBQAAQBAJ&q=%22ge-425%22+computer+1964&pg=SA3-PA15|title=British Commercial Computer Digest: Pergamon Computer Data Series|last=Williams|first=R. H.|date=2014-05-23|publisher=Elsevier|isbn=9781483154527|pages=3/15–20|language=en}}</ref> 455 and 465.<ref>{{Cite web|url=http://www.computerhistory.org/collections/catalog/102686873|title=Compatibles/400 {{!}} 102686873 {{!}} Computer History Museum|website=www.computerhistory.org|language=en|access-date=2018-04-18}}</ref>
GE-400 systems had a word length of [[24-bit|24 bits]] which could contain binary data, four six-bit BCD characters, or four signed decimal digits. GE-400 systems could have up to 32,768 words (132K characters) of [[Magnetic-core memory|magnetic-core memory]] with a cycle time of 2.7 microseconds (435) or 5.1 microseconds (425).  The systems supported up to eight channels for input/output.

The '''GE 412''' (1962)<ref>{{Cite book|url=https://books.google.com/books?id=qmYhAQAAIAAJ&q=%22GE+412%22+1962|title=The European Computer Users Handbook|date=1968|publisher=Computer Consultants.|pages=15|language=en}}</ref> was an incompatible computer system with a 20-bit word length intended for [[Process control|process control]] applications.<ref>{{cite book|last=General Electric Company|title=GE 412 Programming Manual|url=http://bitsavers.trailing-edge.com/pdf/ge/GE-412/PCP56_GE-412_Programming_Manual.pdf}}</ref>

==Unique features== 
GE-400 systems featured a "variable length, relocatable [[Accumulator (computing)|accumulator]]"<ref>{{cite book
 | last = General Electric Company
 | title = GE 425/435 Reference Manual
 | year = 1963
 | pages = 1–12: 1–13
 | url = http://www.bitsavers.org/pdf/ge/GE-4xx/CPB-320_GE425-435_RefMan_Dec63.pdf
 }}</ref> which could be set programmatically to a length of one to four words and relocated to overlay any four adjacent locations in memory (modulo four).  "The accumulator can be moved to the data to be processed, rather than moving the data." 
 
== Successor systems ==
The 400 series was succeeded by the incompatible 36-bit [[Engineering:GE-600 series|GE-600 series]].

==See also==
* [[Engineering:GE-200 series|GE-200 series]]
* [[Engineering:GE-600 series|GE-600 series]]

== References ==
{{Reflist}}

==External links==
*[http://www.computerhistory.org/collections/accession/102646147 GE-400 Time-sharing information systems: Bring a powerful computer to the fingertips of all your people | 102646147 | Computer History Museum]
<!--*http://febcm.club.fr/english/chronoa5.htm-->
*[http://www.feb-patrimoine.com/PROJET/ge400/ge-400.htm General Electric]
*[http://www.histoireinform.com/Histoire/+infos2/chr4infd.htm Le Musée Bull Belgique - Luxembourg: GE 400 (in French)]


[[Category:Transistorized computers]]

{{Sourceattribution|GE-400 series}}