ISO 2047
ISO 2047 (Information processing – Graphical representations for the control characters of the 7-bit coded character set) is a standard for graphical representation of the control characters for debugging purposes, such as may be found in the character generator of a computer terminal; it also establishes a two-letter abbreviation of each control character.[1] The graphics and two-letter codes are essentially unchanged from the 1968 European standard ECMA-17[2] and the 1973 American standard ANSI X3.32-1973.[3] It became an ISO standard in 1975.[1] It is also standardized as GB/T 3911-1983 in China, as KS X 1010[4] in Korea (formerly KS C 5713), and was enacted in Japan as "graphical representation of information exchange capabilities for character" JIS X 0209:1976 (former JIS C 6227) (abolished January 20, 2010).
While the ISO/IEC 646 three-letter abbreviations (such as "ESC"), or caret notation (such as "^[") are still in use, the graphical symbols of ISO 2047 are considered outdated and rare.[5]
Character table
Code (hex) |
Common abbreviation |
Name | Symbol[1][2][6][7][8] | 2-letter abbreviation | |
---|---|---|---|---|---|
00 | NUL | Null | ⎕ | U+2395 | NU |
01 | TC1, SOH | Start of Heading | ⌈ | U+2308 | SH |
02 | TC2, STX | Start of Text | ⊥ | U+22A5 | SX |
03 | TC3, ETX | End of Text | ⌋ | U+230B | EX |
04 | TC4, EOT | End of Transmission | ⌁ | U+2301[9] | ET |
05 | TC5, ENQ | Enquiry | ⊠[lower-alpha 1] | U+22A0 | EQ |
06 | TC6, ACK | Acknowledge | ✓ | U+2713 | AK |
07 | BEL | Bell | ⍾ | U+237E[9] | BL |
08 | FE0, BS | Backspace | ⤺ | —[lower-alpha 2] | BS |
09 | FE1, HT | Horizontal Tabulation | ⪫ | U+2AAB | HT |
0A | FE2, LF | Line Feed | ≡ | U+2261 | LF |
0B | FE3, VT | Vertical Tabulation | ⩛ | U+2A5B | VT |
0C | FE4, FF | Form Feed | ↡ | U+21A1 | FF |
0D | FE5, CR | Carriage Return | ⪪ | U+2AAA | CR |
0E | SO | Shift Out | ⊗ | U+2297 | SO |
0F | SI | Shift In | ⊙ | U+2299 | SI |
10 | TC7, DLE | Data Link Escape | ⊟ | U+229F | DL |
11 | DC1, XON, CON[10] | Device Control 1 | ◷ | U+25F7 | D1 |
12 | DC2, RPT,[10] TAPE[lower-alpha 3] | Device Control 2 | ◶ | U+25F6 | D2 |
13 | DC3, XOF, XOFF | Device Control 3 | ◵ | U+25F5 | D3 |
14 | DC4, COF, KMC,[10] |
Device Control 4 | ◴ | U+25F4 | D4 |
15 | TC8, NAK | Negative Acknowledge | ⍻ | U+237B[9] | NK |
16 | TC9, SYN | Synchronization | ⎍ | U+238D | SY |
17 | TC10, ETB | End of Transmission Block | ⊣ | U+22A3 | EB |
18 | CAN | Cancel | ⧖ | U+29D6 | CN |
19 | EM | End of Medium | ⍿ | U+237F[9] | EM |
1A | SUB | Substitute Character | ␦ | U+2426[12] | SB |
1B | ESC | Escape | ⊖ | U+2296 | EC |
1C | IS4, FS | File Separator | ◰ | U+25F0 | FS |
1D | IS3, GS | Group Separator | ◱ | U+25F1 | GS |
1E | IS2, RS | Record Separator | ◲ | U+25F2 | RS |
1F | IS1 US | Unit Separator | ◳ | U+25F3 | US |
20 | SP | Space | △ | U+25B3 | SP |
7F | DEL | Delete | —[lower-alpha 4] | DT |
Notes
- In ISO 2047, ✠ is the primary glyph and ⊠ is only a fallback, but ECMA-17 lists only ⊠.
- As a best-fit approximation ↖ could be used. Other defensible choices could be ⤺, ↰, ⮢, ⮪, ⮌ or ⮏.
- On the Teletype Model 33 TAPE and
TAPEwould control the tape punch, whereas XON and XOFF would control the reader. ENQ was labelled WRU for 'who are you?'[11] - As a best-fit approximation ▨, 🮙 or ␥ could be used.
References
- "ISO 2047:1975 Information processing – Graphical representations for the control characters of the 7-bit coded character set". ISO. Retrieved 13 April 2020.
- "ECMA-17, Graphic Representation of the Control Characters of the ECMA 7-Bit Coded Character Set for Information Interchange". (withdrawn)
- "American National Standard – Graphic Representation of the Control Characters of American National Standard Code for Information Interchange". American National Standards Institute. 3 July 1973.
- "KS X 1010-2007 Graphical representations control characters for Information interchange".
- Agim Çami, "Control characters in ASCII and Unicode" (PDF). Agim Çami – Computer Architecture web site. 1 July 2019.
- Michael P. Frank (14 September 2006). "A Proposed Set of Mnemonic Symbolic Glyphs for the Visual Representation of C0 Controls and Other Nonprintable ASCII Characters" (PDF). (mirror)
- "Information Representation". 28 August 2016. – This is the site cited by Michael P. Frank
- "Information Technology - Irish 7-bit coded character sets". 13 December 1995. – Note that in this article the glyphs for ENQ, BS, CR and SO are anomalous, possibly to accommodate the low resolution.
- Specifically cited in The Unicode Standard, Version 6.2. Miscellaneous Technical. Range: 2300–23FF.
- Comité Consultatif International Télégraphique et Téléphonique (31 July 1987). Primary Control Set of Data Syntax II of CCITT Rec. T.101 (PDF). ITSCJ/IPSJ. ISO-IR-134.
"Terminals for Telematic Services, International Interworking for Videotex Services". International Telecommunication Union. 11 November 1994. A.3.9 General control characters. - Robert McConnell; James Haynes; Richard Warren (December 2002). "Understanding ASCII Codes". NADCOMM.
- Specifically cited in The Unicode Standard, Version 6.2. Control Pictures. Range: 2400–243F.
External links
- ECMA-17 (Ecma International equivalent)
- BN-76/3101-05 (Polish equivalent)