# Transcode (character encoding)
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> Markdown URL: https://mediated.wiki/source/Transcode_(character_encoding).md
> Source: https://en.wikipedia.org/wiki/Transcode_(character_encoding)
> Source revision: 1337259621
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)
{{Short description|IBM 6-bit data transmission code}}
{{Other uses|Transcode (disambiguation)}}
{{Use dmy dates|date=May 2019|cs1-dates=y}}
'''Six-Bit Transcode''', or '''Six-Bit Transmission Code''', was, for a few years, one of the three [character sets](/source/character_encoding) used by [IBM](/source/IBM) for [Binary Synchronous Communications](/source/Binary_Synchronous_Communications). Transmission using 6-bit Transcode had higher throughput than transmission using 8-bit [EBCDIC](/source/EBCDIC) or [ASCII](/source/ASCII), provided that the data to be transmitted used a limited set of 48 [characters](/source/character_(computing)).
The [IBM 2780](/source/IBM_2780) data transmission terminal was announced with Transcode support in 1967. Its successor, the [IBM 3780](/source/IBM_2780) [data communication](/source/data_communication) terminal, announced in 1972, dropped Transcode support and added a "space compression" option.
Transcode is a [six-bit character code](/source/six-bit_character_code). It relates to IBM's [punched card code](/source/punched_card_code) but, like EBCDIC, it is not [BCD](/source/BCD_(character_encoding)). Its 64 values consist of the 26 uppercase letters, 10 numbers, 11 symbols, [space](/source/space_(character)), and 16 [control character](/source/control_character)s. Its 48 printable characters are ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 .'-/@#$%&*⌑; it cannot represent ,:;!?"()[]<>+^=_\`{}|~. Characters are transmitted with [odd parity](/source/odd_parity). The 2780 cannot use the 16 control characters as data characters in Transcode mode.[{{cite book |last=IBM Corporation |title=Component Description: IBM 2780 Communications Terminal |year=1971 |url=http://www.bitsavers.org/pdf/ibm/2780/GA27-3005-3-2780_Data_Terminal_Description_Aug71.pdf |url-status=live |archive-url=https://web.archive.org/web/20200726231256/http://www.bitsavers.org/pdf/ibm/2780/GA27-3005-3-2780_Data_Terminal_Description_Aug71.pdf |archive-date=2020-07-26}}]
==Code table==
{|{{chset-table-header1|Six-Bit Transcode}}
|-
|{{chset-left1|0x}}
|{{chset-ctrl1|U+0001 START OF HEADING|{{Control code link|SOH}}}}
|{{chset-cell1|U+0041 LATIN CAPITAL LETTER A|[A](/source/A)|1}}
|{{chset-cell1|U+0042 LATIN CAPITAL LETTER B|[B](/source/B)|2}}
|{{chset-cell1|U+0043 LATIN CAPITAL LETTER C|[C](/source/C)|3}}
|{{chset-cell1|U+0044 LATIN CAPITAL LETTER D|[D](/source/D)|4}}
|{{chset-cell1|U+0045 LATIN CAPITAL LETTER E|[E](/source/E)|5}}
|{{chset-cell1|U+0046 LATIN CAPITAL LETTER F|[F](/source/F)|6}}
|{{chset-cell1|U+0047 LATIN CAPITAL LETTER G|[G](/source/G)|7}}
|{{chset-cell1|U+0048 LATIN CAPITAL LETTER H|[H](/source/H)|8}}
|{{chset-cell1|U+0049 LATIN CAPITAL LETTER I|[I](/source/I)|9}}
|{{chset-ctrl1|U+0002 START OF TEXT|{{Control code link|STX}}}}
|{{chset-cell1|U+002E FULL STOP|[.](/source/Full_stop)}}
|{{chset-cell1|U+2311 SQUARE LOZENGE|[⌑](/source/Lozenge_(shape))}}
|{{chset-ctrl1|U+0007 BELL|{{Control code link|BEL}}}}
|{{chset-ctrl1|U+001A SUBSTITUTE|{{Control code link|SUB}}}}
|{{chset-ctrl1|U+0017 END OF TRANSMISSION BLOCK|{{Control code link|ETB}}}}
|-
|{{chset-left1|1x}}
|{{chset-cell1|U+0026 AMPERSAND|[&](/source/Ampersand)}}
|{{chset-cell1|U+004A LATIN CAPITAL LETTER J|[J](/source/J)}}
|{{chset-cell1|U+004B LATIN CAPITAL LETTER K|[K](/source/K)}}
|{{chset-cell1|U+004C LATIN CAPITAL LETTER L|[L](/source/L)}}
|{{chset-cell1|U+004D LATIN CAPITAL LETTER M|[M](/source/M)}}
|{{chset-cell1|U+004E LATIN CAPITAL LETTER N|[N](/source/N)}}
|{{chset-cell1|U+004F LATIN CAPITAL LETTER O|[O](/source/O)}}
|{{chset-cell1|U+0050 LATIN CAPITAL LETTER P|[P](/source/P)}}
|{{chset-cell1|U+0051 LATIN CAPITAL LETTER Q|[Q](/source/Q)}}
|{{chset-cell1|U+0052 LATIN CAPITAL LETTER R|[R](/source/R)}}
|{{chset-ctrl1|U+0020 SPACE|[SP](/source/Space_character)}}
|{{chset-cell1|U+0024 DOLLAR SIGN|[$](/source/Dollar_sign)}}
|{{chset-cell1|U+002A ASTERISK|[*](/source/Asterisk)}}
|{{chset-ctrl1|U+001F INFORMATION SEPARATOR ONE|{{Control code link|US|IUS}}/
{{Control code link|IUS/ITB|ITB}}|style=line-height:1}}
|{{chset-ctrl1|U+0004 END OF TRANSMISSION|{{Control code link|EOT}}}}
|{{chset-ctrl1|U+0010 DATA LINK ESCAPE|{{Control code link|DLE}}}}
|-
|{{chset-left1|2x}}
|{{chset-cell1|U+002D HYPHEN-MINUS|[-](/source/Hyphen-minus)}}
|{{chset-cell1|U+002F SOLIDUS|[/](/source/Slash_(punctuation))}}
|{{chset-cell1|U+0053 LATIN CAPITAL LETTER S|[S](/source/S)}}
|{{chset-cell1|U+0054 LATIN CAPITAL LETTER T|[T](/source/T)}}
|{{chset-cell1|U+0055 LATIN CAPITAL LETTER U|[U](/source/U)}}
|{{chset-cell1|U+0056 LATIN CAPITAL LETTER V|[V](/source/V)}}
|{{chset-cell1|U+0057 LATIN CAPITAL LETTER W|[W](/source/W)}}
|{{chset-cell1|U+0058 LATIN CAPITAL LETTER X|[X](/source/X)}}
|{{chset-cell1|U+0059 LATIN CAPITAL LETTER Y|[Y](/source/Y)}}
|{{chset-cell1|U+005A LATIN CAPITAL LETTER Z|[Z](/source/Z)}}
|{{chset-ctrl1|U+001B ESCAPE|{{Control code link|ESC}}}}
|{{chset-cell1|U+0027 APOSTROPHE|['](/source/Apostrophe)}}
|{{chset-cell1|U+0025 PERCENT SIGN|[%](/source/Percent_sign)}}
|{{chset-ctrl1|U+0005 ENQUIRY|{{Control code link|ENQ}}}}
|{{chset-ctrl1|U+0003 END OF TEXT|{{Control code link|ETX}}}}
|{{chset-ctrl1|U+0009 CHARACTER TABULATION|{{Control code link|HT}}}}
|-
|{{chset-left1|3x}}
|{{chset-cell1|U+0030 DIGIT ZERO|[0](/source/0)}}
|{{chset-cell1|U+0031 DIGIT ONE|[1](/source/1)}}
|{{chset-cell1|U+0032 DIGIT TWO|[2](/source/2)}}
|{{chset-cell1|U+0033 DIGIT THREE|[3](/source/3)}}
|{{chset-cell1|U+0034 DIGIT FOUR|[4](/source/4)}}
|{{chset-cell1|U+0035 DIGIT FIVE|[5](/source/5)}}
|{{chset-cell1|U+0036 DIGIT SIX|[6](/source/6)}}
|{{chset-cell1|U+0037 DIGIT SEVEN|[7](/source/7)}}
|{{chset-cell1|U+0038 DIGIT EIGHT|[8](/source/8)}}
|{{chset-cell1|U+0039 DIGIT NINE|[9](/source/9)}}
|{{chset-ctrl1|U+0016 SYNCHRONOUS IDLE|{{Control code link|SYN}}}}
|{{chset-cell1|U+0023 NUMBER SIGN|[#](/source/Number_sign)}}
|{{chset-cell1|U+0040 COMMERCIAL AT|[@](/source/At_sign)}}
|{{chset-ctrl1|U+0015 NEGATIVE ACKNOWLEDGE|{{Control code link|NAK}}}}
|{{chset-ctrl1|U+0019 END OF MEDIUM|{{Control code link|EM }}}}
|{{chset-ctrl1|U+007F DELETE|{{Control code link|DEL}}}}
|}
==Code table (from 2780 manual)==
{| class="wikitable" style="font-family: 'Courier New';"
! Character
!! [Punched card](/source/Punched_card)
code !! 6-bit
transcode !! Hex
|-
| SOH || 12-9-1 || P || 00
|-
| A || 12-1 || 5 || 01
|-
| B || 12-2 || 4 || 02
|-
| C || 12-3 || 4 5 P || 03
|-
| D || 12-4 || 3 || 04
|-
| E || 12-5 || 3 5 P || 05
|-
| F || 12-6 || 3 4 P || 06
|-
| G || 12-7 || 3 4 5 || 07
|-
| H || 12-8 || 2 || 08
|-
| I || 12-9 || 2 5 P || 09
|-
| STX || 12-9-2 || 2 4 P || 0A
|-
| . || 12-8-3 || 2 4 5 || 0B
|-
| ⌑ || 12-8-4 || 2 3 P || 0C
|-
| BEL || 0-9-8-7 || 2 3 5 || 0D
|-
| Sub || 9-8-7 || 2 3 4 || 0E
|-
| ETB || 0-9-6 || 2 3 4 5 P || 0F
|-
| & || 12 || 1 || 10
|-
| J || 11-1 || 1 5 P || 11
|-
| K || 11-2 || 1 4 P || 12
|-
| L || 11-3 || 1 4 5 || 13
|-
| M || 11-4 || 1 3 P || 14
|-
| N || 11-5 || 1 3 5 || 15
|-
| O || 11-6 || 1 3 4 || 16
|-
| P || 11-7 || 1 3 4 5 P || 17
|-
| Q || 11-8 || 1 2 P || 18
|-
| R || 11-9 || 1 2 5 || 19
|-
| Space || no punch || 1 2 4 || 1A
|-
| $ || 11-8-3 || 1 2 4 5 P || 1B
|-
| * || 11-8-4 || 1 2 3 || 1C
|-
| US || 11-9-8-7 || 1 2 3 5 P || 1D
|-
| EOT || 9-7 || 1 2 3 4 P || 1E
|-
| DLE || 12-11-9-8-1 || 1 2 3 4 5 || 1F
|-
| - || 11 || 0 || 20
|-
| / || 0-1 || 0 5 P || 21
|-
| S || 0-2 || 0 4 P || 22
|-
| T || 0-3 || 0 4 5 || 23
|-
| U || 0-4 || 0 3 P || 24
|-
| V || 0-5 || 0 3 5 || 25
|-
| W || 0-6 || 0 3 4 || 26
|-
| X || 0-7 || 0 3 4 5 P || 27
|-
| Y || 0-8 || 0 2 P || 28
|-
| Z || 0-9 || 0 2 5 || 29
|-
| ESC || 0-9-7 || 0 2 4 || 2A
|-
| ' || 0-8-3 || 0 2 4 5 P || 2B
|-
| % || 0-8-4 || 0 2 3 || 2C
|-
| ENQ || 0-9-8-5 || 0 2 3 5 P || 2D
|-
| ETX || 12-9-3 || 0 2 3 4 P || 2E
|-
| HT || 12-9-5 || 0 2 3 4 5 || 2F
|-
| 0 || 0 || 0 1 P || 30
|-
| 1 || 1 || 0 1 5 || 31
|-
| 2 || 2 || 0 1 4 || 32
|-
| 3 || 3 || 0 1 4 5 P || 33
|-
| 4 || 4 || 0 1 3 || 34
|-
| 5 || 5 || 0 1 3 5 P || 35
|-
| 6 || 6 || 0 1 3 4 P || 36
|-
| 7 || 7 || 0 1 3 4 5 || 37
|-
| 8 || 8 || 0 1 2 || 38
|-
| 9 || 9 || 0 1 2 5 P || 39
|-
| SYN || 9-2 || 0 1 2 4 P || 3A
|-
| # || 8-3 || 0 1 2 4 5 || 3B
|-
| @ || 8-4 || 0 1 2 3 P || 3C
|-
| NAK || 9-8-5 || 0 1 2 3 5 || 3D
|-
| EM || 11-9-8-1 || 0 1 2 3 4 || 3E
|-
| DEL || 12-9-7 || 0 1 2 3 4 5 P || 3F
|}
==Devices using Transcode==
* [IBM 2701](/source/IBM_2701) Data Adapter Unit
* [IBM 2703](/source/IBM_2703) Transmission Control
* [IBM 2780](/source/IBM_2780%2F3780) Data Transmission Terminal
* [IBM System/370](/source/IBM_System%2F370) model 135 Integrated Communications Adapter (ICA)
==References==
{{Reflist}}
{{Character encodings}}
Category:Character encoding
Category:IBM computer hardware
---
Adapted from the Wikipedia article [Transcode (character encoding)](https://en.wikipedia.org/wiki/Transcode_(character_encoding)) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Transcode_(character_encoding)?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.