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(such as "ESC"), or caret notation (such as "^[") are still in use, the graphical symbols of ISO 2047 are considered outdated and rare.[5]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
edit| 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 | ⊠[a] | U+22A0 | EQ |
| 06 | TC6, ACK | Acknowledge | ✓ | U+2713 | AK |
| 07 | BEL | Bell | ⍾ | U+237E[9] | BL |
| 08 | FE0, BS | Backspace | ⤺ | —[b] | 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[c] | 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 | —[d] | DT | |
Notes
edit- ^ 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 ⮏.
- ^ a b 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
edit- ^ a b c "ISO 2047:1975 Information processing – Graphical representations for the control characters of the 7-bit coded character set". ISO. Archived from the original on 2 August 2020. Retrieved 13 April 2020.
- ^ a b "ECMA-17, Graphic Representation of the Control Characters of the ECMA 7-Bit Coded Character Set for Information Interchange". Archived from the original on 2023-12-02. Retrieved 2024-05-08. (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".[permanent dead link]
- ^ Agim Çami, "Control characters in ASCII and Unicode" (PDF). Agim Çami – Computer Architecture web site. 1 July 2019. Archived (PDF) from the original on 6 October 2021. Retrieved 5 August 2020.
- ^ 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). Archived (PDF) from the original on 2 July 2023. Retrieved 8 May 2024. (mirror)
- ^ "Information Representation". 28 August 2016. Archived from the original on 1 August 2020. Retrieved 26 April 2020. – This is the site cited by Michael P. Frank
- ^ "Information Technology - Irish 7-bit coded character sets". 13 December 1995. Archived from the original on 8 May 2024. Retrieved 26 April 2020. – Note that in this article the glyphs for ENQ, BS, CR and SO are anomalous, possibly to accommodate the low resolution.
- ^ a b c d Specifically cited in "Miscellaneous Technical. Range: 2300–23FF" (PDF). The Unicode Standard. Archived (PDF) from the original on 2019-12-30.
- ^ a b c 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. Archived from the original on 2 July 2023. Retrieved 8 May 2024. - ^ Robert McConnell; James Haynes; Richard Warren (December 2002). "Understanding ASCII Codes". NADCOMM. Archived from the original on 2023-09-26. Retrieved 2024-05-08.
- ^ Specifically cited in "Control Pictures. Range: 2400–243F" (PDF). The Unicode Standard. Archived (PDF) from the original on 2019-01-18.
External links
edit- ECMA-17 (Ecma International equivalent)
- BN-76/3101-05 (Polish equivalent)