Six-bit character code: Difference between revisions

Revision as of 17:18, 1 June 2025

Latest revision as of 09:29, 24 August 2025

(2 intermediate revisions by one other user not shown)

Line 1:

{{Short description|Computer encoding of characters}}

{{Use dmy dates|date=May 2019|cs1-dates=y}}

A '''six-bit character code''' is a [[character encoding]] designed for use on computers with [[word length]]s a multiple of 6. Six bits can only encode 64 distinct characters, so these codes generally include only the upper-case letters, the numerals, some punctuation characters, and sometimes control characters. The [[IBM 7 track|7-track]] [[Magnetic -tape data storage|magnetic tape]] format was developed to store data in such codes, along with an additional [[parity bit]].

==Types of six-bit codes==

Line 18:

The TTS code had two pairs of shift codes allowing a total of four shift states. The first operated much like a keyboard's shift key and selected between a lower-case and digits repertoire, and an upper-case and symbols one. A second pair of Linotype-specific "lower rail" and "upper rail" shift codes would select an alternate (usually italic) font.

===BCD six-bit codecodes===

Six-bit [[BCD (6-bitcharacter encoding)|BCD]] code wascodes thewere adaptationadaptations of the [[punched card code]] to [[binary code]]. [[IBM]] applied the terms ''binary-coded decimal'' and ''BCD'' to the variations of BCD ''alphamerics'' used in most early IBM computers, including the [[IBM 1620]], [[IBM 1400 series]], and non-[[IBM 700/7000 series#Decimal architecture (7070/7072/7074)|decimal architecture]] members of the [[IBM 700/7000 series]].

===COBOL databases six-bit code===

Line 269:

===AIS SixBit ASCII===

{|{{chset-table-header1|SixBit ASCII (used byThe [[Automaticautomatic identification system|AIS]] (AIS) uses this code.<ref name='Raymond'>{{cite web |url=https://gpsd.gitlab.io/gpsd/AIVDM.html#_ais_payload_data_types |title=AIVDM/AIVDO protocol decoding |at=AIS Payload Data Types |access-date=2024-03-14 |author-last=Raymond |author-first=Eric S. |date=2023-06-24}}</ref>}}

{|{{chset-table-header1|AIS SixBit ASCII}}

|-

|{{chset-left1|0x}}