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==Features==
The Model 50 implements the complete [[IBM System/360 architecture|System/360 "universal instruction set" architecture]], including floating-point, decimal, and character operations as standard features. The "direct control" instructions are an optional feature. Optional logic, microcode and software providing compatibility with either the [[IBM 1410|IBM 1410/7010]] or [[IBM 7070|7070/7074]] systems is available.
An [[IBM 1050|IBM 1052]] printer/keyboard for use as an operator's console is optional. The I/O options include one [[channel-to-channel adapter]] (CTCA) and up to three [[Channel I/O|selector channel]]s. A [[Channel I/O|multiplexer channel]] for attachment of slow-speed devices is standard on all models. The F50 has 64 subchannels, so it can attach up to 64 slow-speed devices on its multiplexer channel. The other models have 128 subchannels. This can optionally increase to 256 subchannels on the H50 and I50.<ref name="FuncChar">{{cite book|publisher=IBM|title=IBM System 360 Model 50 Functional Characteristics|id=A22-6898-1|date=1967|url=http://www.bitsavers.org/pdf/ibm/360/funcChar/A22-6898-1_360-50_funcChar_1967.pdf|accessdate=Sep 20, 2016}}</ref>
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The Model 50 uses a 90 bit (or 85 bit, depending on definition) "horizontal microcode" instruction format, with each word containing 15 (or 25) separate fields.<ref>{{cite web|last1=Smotherman|first1=Mark|title=A Brief History of Microprogramming|url=http://ed-thelen.org/comp-hist/MicroprogrammingABriefHistoryOf.pdf|accessdate=Sep 26, 2015}}</ref> There are 2816 words of microcode storage.<ref>{{cite book|last1=Kent|first1=Allen (ed)|last2=Williams|first2=James G. (ed)|title=Encyclopedia of Computer Science and Technology volume 28|date=1993|publisher=CRC Press|isbn=978-0-8247-2281-4|page=39|url=https://books.google.com/books?id=EjWV8J8CQEYC&printsec=frontcover#v=onepage&q&f=false|accessdate=Sep 26, 2015}}</ref>
Read-only control storage for microcode employs "balanced capacitor technology" (BCROS) with a cycle time of 500 nanoseconds, designed by Anthony Proudman in [[IBM Hursley|IBM's Hursley laboratory]] and implemented by Fernando "Fred" Neves. This technology uses two [[capacitor]]s to represent each bit.
[[File:IBM 360-50, ZETO ZOWAR (I197703).jpg|thumb|right|B&W closeup of 360/50 console]]
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