NCR 315
an obsolete second-generation computer
The NCR 315 Data Processing System, released in January 1962 by NCR, is a second-generation computer. All printed circuit boards use resistor–transistor logic (RTL) to create the various logic elements. The magnetic-core memory is divided into 12-bit addressable units called slabs. The instructions can use a memory slab as either two 6-bit alphanumeric characters or as three 4-bit BCD digits. Basic memory is 5000 slabs (10,000 characters or 15,000 decimal digits), which is expandable to a maximum of 40,000 slabs (80,000 characters or 120,000 decimal digits) in four refrigerator-size cabinets. The main processor includes three cabinets and a console section that houses the power supply, keyboard, output writer (an IBM electric typewriter), and a panel with lights that indicate the current status of the program counter, registers, arithmetic accumulator, and system errors. Input/Output is by direct parallel connections to each type of peripheral through a two-cable bundle with 1-inch-thick cables. Some devices like magnetic tape and the CRAM are daisy-chained to allow multiple drives to be connected.
The central processor (315 Data Processor) weighed about 1,325 pounds (601 kg).
Later models in this series include the 315-100 and the 315-RMC (Rod Memory Computer).
“NCR 315” enters the record as an obsolete second-generation computer. Crown Archives preserves that source wording while asking what obsolete, second-generation and computer can confirm, complicate or overturn.
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“NCR 315” is worth following because a concise public description often conceals a longer documentary argument. Here, obsolete, second-generation and computer provides the most credible route into that argument.
Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Jul 28, 2026. The linked authority identifier is Q17070977. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1962.
The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
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This entry incorporates text from “NCR 315” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.