Syllable (computing)

In computing, a syllable is a name for a platform-dependent unit of information storage. Depending on the target hardware, various bit widths (and sometimes internal groupings) are associated with it. Commonly used in the 1960s and 1970s, the term has mostly fallen into disuse in favour of terms like byte or word.

Examples:

• 3-bit syllables: some experimental CISC designs^[1][2]
• 8-bit syllables: English Electric KDF9 (represented as syllabic octals and also called slob-octals^[3][4] or slobs in this context)^[5] and Burroughs large systems (see also: Burroughs B6x00-7x00 instruction set)
• 12-bit syllables: NCR computers such as the NCR 315^[6] (also called slabs in this context)^[6][7][8] and Burroughs large systems
• 13-bit syllables: Saturn Launch Vehicle Digital Computer (LVDC)^[9] and Gemini Spacecraft On-Board Computer (OBC)^[10]

See also

• Byte
• Catena (computing)
• Instruction syllable
• Nibble
• Opcode
• Opstring
• Parcel (computing)
• Syllable (in linguistics)
• Word (computer architecture)

References

1. Jones, Douglas W. (2016) [2012]. "A Minimal CISC". Computer Architecture On-Line Collection. Iowa City, USA: The University of Iowa, Department of Computer Science. from the original on 2016-05-28. Retrieved 2016-05-28.
2. Jones, Douglas W. (June 1988). "A Minimal CISC". ACM SIGARCH Computer Architecture News. 16 (3). New York, USA: Association for Computing Machinery (ACM): 56–63. doi:10.1145/48675.48684. S2CID 17280173.
3. Beard, Bob (Autumn 1997) [1996-10-01]. "The KDF9 Computer — 30 Years On" (PDF). Resurrection - The Bulletin of the Computer Conservation Society. No. 18. Computer Conservation Society (CCS). pp. 7–15 [9, 11]. ISSN 0958-7403. (PDF) from the original on 2020-07-27. Retrieved 2020-07-27. (NB. This is an edited version of a talk given to North West Group of the Society at the Museum of Science and Industry, Manchester, UK on 1996-10-01. It mentions the term "slob" and "slob-octal" as equivalent to "syllabic octal".)
4. "Architecture of the English Electric KDF9 computer" (PDF). Version 1. Computer Conservation Society (CCS). September 2009. CCS-N4X2. (PDF) from the original on 2020-04-04. Retrieved 2020-07-27. (NB. Refers to Beard's 1997 article.)
5. English Electric KDF9: Very high speed data processing system for Commerce, Industry, Science (PDF) (Product flyer). English Electric. c. 1961. Publication No. DP/103. 096320WP/RP0961. (PDF) from the original on 2020-07-27. Retrieved 2020-07-27.
6. Schneider, Carl (2013) [1970]. Datenverarbeitungs-Lexikon [Lexicon of information technology] (in German) (softcover reprint of hardcover 1st ed.). Wiesbaden, Germany: Springer Fachmedien Wiesbaden GmbH / Betriebswirtschaftlicher Verlag Dr. Th. Gabler GmbH. pp. 201, 308. doi:10.1007/978-3-663-13618-7. ISBN 978-3-409-31831-0. ISBN 3-663-13618-3 / ISBN 978-3-663-13618-7 (ebook). Retrieved 2016-05-24. pp. 201, 308: slab, Abk. aus syllable = Silbe, die kleinste adressierbare Informationseinheit für 12 bit zur Übertragung von zwei Alphazeichen oder drei numerischen Zeichen. (NCR) […] Hardware: Datenstruktur: NCR 315-100 / NCR 315-RMC; Wortlänge: Silbe; Bits: 12; Bytes: –; Dezimalziffern: 3; Zeichen: 2; Gleitkommadarstellung: fest verdrahtet; Mantisse: 4 Silben; Exponent: 1 Silbe (11 Stellen + 1 Vorzeichen) [slab, abbr. for syllable = syllable, smallest addressable information unit for 12 bits for the transfer of two alphabetical characters or three numerical characters. (NCR) […] Hardware: Data structure: NCR 315-100 / NCR 315-RMC; Word length: Syllable; Bits: 12; Bytes: –; Decimal digits: 3; Characters: 2; Floating point format: hard-wired; Significand: 4 syllables; Exponent: 1 syllable (11 digits + 1 prefix)]
7. "315 Electronic Data Processing System" (PDF). NCR. November 1965. NCR MPN ST-5008-15. (PDF) from the original on 2016-05-24. Retrieved 2015-01-28.
8. Bardin, Hillel (1963). "NCR 315 Seminar" (PDF). Computer Usage Communique. 2 (3). (PDF) from the original on 2016-05-24.
9. Burkey, Ronald (2009-08-21). "Virtual AGC — AGS — LVDC — Gemini: Launch Vehicle Digital Computer (LVDC): Saturn IB and Saturn V Rockets". from the original on 2016-05-28. Retrieved 2016-05-28.
10. Burkey, Ronald (2010-09-06) [2011]. "Gemini Spacecraft Computer (OBC): Layout of Memory Words". from the original on 2016-05-28. Retrieved 2016-05-28.