This article is about the Videotex character sets defined by ITU T.101. For the Videotex (Viewdata and Teletext) character sets defined by ETS 300 706, see Teletext character set.
The character sets used by Videotex are based, to greater or lesser extents, on ISO/IEC 2022. Three Data Syntax systems are defined by ITU T.101, corresponding to the Videotex systems of different countries.
Data Syntax 1 is defined in Annex B of T.101:1994. It is based on the CAPTAIN system used in Japan. Its graphical sets include JIS X 0201 and JIS X 0208.
The following G-sets are available through ISO/IEC 2022-based designation escapes:[1]: AnxB.2.3
The mosaic sets supply characters for use in semigraphics.
Videotex Mosaic set: First Mosaic set for Data Syntax 1 (ISO-IR-137; partial Unicode mapping)[2]
0
1
2
3
4
5
6
7
8
9
A
B
C
D
E
F
0x
1x
2x
▖
�
�
▟
�
�
�
�
�
�
�
🮛
�
�
�
3x
▄
▗
�
�
▙
�
�
�
�
�
�
�
🮚
�
�
�
4x
5x
6x
🭒
🭓
🭔
🭕
🭖
◥
🭗
🭘
🭙
🭚
🭛
🭜
🭬
🭭
7x
🭝
🭞
🭟
🭠
🭡
◤
🭢
🭣
🭤
🭥
🭦
🭧
🭮
🭯
� Not in Unicode
Videotex Mosaic set: Second Mosaic set for Data Syntax 1 (ISO-IR-71)[3]
0
1
2
3
4
5
6
7
8
9
A
B
C
D
E
F
0x
1x
2x
🬀
🬁
🬂
🬃
🬄
🬅
🬆
🬇
🬈
🬉
🬊
🬋
🬌
🬍
🬎
3x
🬏
🬐
🬑
🬒
🬓
▌
🬔
🬕
🬖
🬗
🬘
🬙
🬚
🬛
🬜
🬝
4x
🬼
🬽
🬾
🬿
🭀
◣
🭁
🭂
🭃
🭄
🭅
🭆
🭨
🭩
🭰
🮕
5x
🭇
🭈
🭉
🭊
🭋
◢
🭌
🭍
🭎
🭏
🭐
🭑
🭪
🭫
🭵
█
6x
🬞
🬟
🬠
🬡
🬢
🬣
🬤
🬥
🬦
🬧
▐
🬨
🬩
🬪
🬫
🬬
7x
🬭
🬮
🬯
🬰
🬱
🬲
🬳
🬴
🬵
🬶
🬷
🬸
🬹
🬺
🬻
Data Syntax 2
Data Syntax 2 is defined in Annex C of T.101:1994. It corresponds to some European Videotex systems such as CEPT T/CD 06-01. The graphical character coding of Data Syntax 2 is based on T.51.
The default G2 set of Data Syntax 2 is based on an older version of T.51, lacking the non-breaking space, soft hyphen, not sign (¬) and broken bar (¦) present in the current version, but adding a dialytika tonos (΅—combining form is U+0344) at the beginning of the row of diacritical marks for combination with codes from a Greek primary set.[5] An umlaut diacritic code distinct from the diaeresis code, as included in some versions of T.61, is also sometimes included.[6]
The default G1 set is the second mosaic set, corresponding roughly to the second mosaic set of Data Syntax 1.[1]: AnxCpt1/TableC.11 The default G3 set is the third mosaic set, matching the first mosaic set of Data Syntax 1 for 0x60 through 0x6D and 0x70 through 0x7D, and otherwise differing.[1]: AnxCpt1/TableC.12 The first mosaic set matches the second except for 0x40 through 0x5E: 0x40 through 0x5A follow ASCII (supplying uppercase letters), whereas the remainder are national variant characters; the displaced full block is placed at 0x7F.[1]: AnxCpt1/TableC.10
Videotex Mosaic set: First Mosaic set for Data Syntax 2[1]: AnxCpt1/TableC.10
Data Syntax 3 is defined in Annex D of T.101:1994. The graphical character coding of Data Syntax 3 is based on T.51.
The supplementary set for Data Syntax 3 is based on an older version of T.51, lacking the non-breaking space, soft hyphen, not sign (¬) and broken bar (¦) present in the current version, and allocating non-spacing marks for a "vector overbar" and solidus and several semigraphic characters to unallocated space in that set.
Differences from T.51 (1988 edition, first supplementary set)
C0 control codes
C0 control codes for Videotex differ from ASCII as shown in the table below. The NUL, BEL, SO (LS1), SI (LS0) and ESC codes are also available in some or all data syntaxes, but without change in name or semantic from ASCII.[8][9][10]
Moves cursor one position backward. If it is at the start of the line, moves it to the end of the line and back one line. This retains one possible semantic of the ASCII BS.
Moves cursor one line forward. If it is at the last line of the screen, moves it to the first line unless Data Syntax 3 scroll mode is active. This retains one possible semantic of the ASCII LF.
Resets entire display to spaces with default display attributes and returns the cursor to its initial position. In Data Syntax 1, also resets macros and DRCS. This retains one possible semantic of the ASCII FF.
Moves the cursor to the start of the line. In Data Syntax 3, may instead move it to the start of the active field if it is entirely within it. This retains one possible semantic of the ASCII CR.
In Data Syntax 2, fill the rest of the current line (after the current position) with spaces (compare EL). In Data Syntax 1 and 3, immediately stop all running macros. Contrast the semantic of basic ASCII CAN.
Followed by two bytes (from 0x40 to 0x7F; may also be from 0xA0 to 0xFF in Data Syntax 3) respectively giving a row and column address in their low six bits. Compare CUP and HVP.
Resets all display attributes (including ISO 2022 state, domain, text parameters, textures, colour mode but not macros, DRCS or programmable masks), then moves the cursor to a specified position. Followed by two bytes (from 0x40 to 0x7F; may also be from 0xA0 to 0xFF in Data Syntax 3) respectively giving a row and column address in their low six bits. Compare RIS.
Followed by two or four bytes (from 0x40 to 0x7F) giving a row and column address in their low six bits. Four bytes are used if there are more than 63 rows and columns, with the most significant six bits being first for each parameter. Compare CUP and HVP. If the following byte is not in the range of 0x40 to 0x7F, indicates a switch to another coding scheme (contrast DOCS).
C1 control codes
The following specialised C1 control codes are used in Videotex. There are four registered sets, with some differences between them.
ABK, Alpha Black. Switch to alphabetic, black foreground.
DEFM, Define Macro. Next character (from 0x20 to 0x7F) gives macro name, rest is stored as part of macro until another DEF* or an END.
0x81
ESC 0x41 (A)
RDF, Red Foreground.
ANR, Alpha Red. Switch to alphabetic, red foreground.
DEFP, Define P-Macro. Like DEFM, but simultaneously defines and executes the macro.
0x82
ESC 0x42 (B)
GRF, Green Foreground.
ANG, Alpha Green. Switch to alphabetic, green foreground.
DEFT, Define Transmit-Macro. Like DEFM but defines a macro to be transmitted, not executed.
0x83
ESC 0x43 (C)
YLF, Yellow Foreground.
ANY, Alpha Yellow. Switch to alphabetic, yellow foreground.
DEFD, Define DRCS. Defines a character in the Dynamically Redefinable Character Set. Expected to be followed by the character code defined (from 0x20 to 0x7F) unless it terminates a previous DEFD, in which case it defines the next code. Terminated by another DEF* or an END
0x84
ESC 0x44 (D)
BLF, Blue Foreground.
ANB, Alpha Blue. Switch to alphabetic, blue foreground.
DEFX, Define Texture. Defines a texture mask. Expected to be followed by the texture mask ID defined (from 0x40 to 0x44). Terminated by another DEF* or an END
0x85
ESC 0x45 (E)
MGF, Magenta Foreground.
ANM, Alpha Magenta. Switch to alphabetic, magenta foreground.
END, End. Terminates a macro, DRCS character or texture definition. Also used in unprotected fields.
0x86
ESC 0x46 (F)
CNF, Cyan Foreground.
ANC, Alpha Cyan. Switch to alphabetic, cyan foreground.
REP, Repeat. Repeats preceding spacing graphical character a number of times specified by the following byte (from 0x40 to 0x7F).
0x87
ESC 0x47 (G)
WHF, White Foreground.
ANW, Alpha White. Switch to alphabetic, white foreground.
REPE, Repeat to End of Line. Repeats preceding spacing graphical character until the end of the line is reached.
0x88
ESC 0x48 (H)
SSZ, Small Size. Characters half normal width and height
FSH, Flashing. Characters displayed flashing between foreground and background.
REVV, Reverse Video. Enables reverse video mode.
0x89
ESC 0x49 (I)
MSZ, Medium Size. Characters normal height, half normal width
STD, Steady. Terminates flashing.
NORV, Normal Video. Disables reverse video mode.
0x8A
ESC 0x4A (J)
NSZ, Normal Size. Characters normal width and height.
SMTX, Small Text. Text size 1/80 of screen width and 5/128 of screen height.
0x8B
ESC 0x4B (K)
SZX, Size Control. Followed by a one-byte parameter. 0x41 means double height (DBH), 0x44 means double width (DBW), 0x45 means doubled width and height (DBS).[1]: AnxB.3.2.2
SBX, Start Box. Defines a non-alphanumeric area, with transparent background. Terminated by EBX.
METX, Medium Text. Text size 1/32 of screen width and 3/64 of screen height.
0x8C
ESC 0x4C (L)
(not used)
NSZ, Normal Size. Characters normal width and height.
NOTX, Normal Text. Text size 1/40 of screen width and 5/128 of screen height.
0x8D
ESC 0x4D (M)
(not used)
DBH, Double Height. Characters normal width and double normal height. Inactive on top line.
DBH, Double Height. Characters normal width and double normal height. Inactive on bottom line.
DBH, Double Height. Text size 1/40 of screen width and 5/64 of screen height.
0x8E
ESC 0x4E (N)
CON, Cursor On. Makes cursor visible.
DBW, Double Width. Characters normal height and double normal width. Inactive in last position of line.
BSTA, Blink Start.
0x8F
ESC 0x4F (O)
COF, Cursor Off. Makes cursor invisible.
DBS, Double Size. Characters normal height and double normal width. Inactive on top line or in last position of line.
DBS, Double Size. Characters normal height and double normal width. Inactive on bottom line or in last position of line.
DBS, Double Size. Text size 1/20 of screen width and 5/64 of screen height.
0x90
ESC 0x50 (P)
COL, Background or Foreground Colour. Takes a one-byte parameter. 0x48–0x4F sets a reduced intensity foreground. 0x50–0x57 sets background colour. 0x58–0x5F sets a reduced intensity background. Colour order is the same as that of the individual foreground colour controls (black, red, green, yellow, blue, magenta, cyan, white), but transparent takes the place of reduced intensity black.[1]: AnxB.3.2.1
BKB, Black Background.
MBK, Mosaic Black. Switch to mosaic, black foreground.
PRO, Protect. Makes all character fields within the active field protected.
0x91
ESC 0x51 (Q)
FLC, Flashing Control. Takes one parameter: 0x40 for "normal" flashing, 0x41 through 0x47 for other flashing modes, 0x4F for steady (terminate flashing).[1]: AnxB.3.2.4
RDB, Red Background.
MSR, Mosaic Red. Switch to mosaic, red foreground.
(EDC1, not used)
0x92
ESC 0x52 (R)
CDC, Conceal Display Control. Takes a one-byte parameter defining conceal display attributes, which can make text invisible until user interaction. 0x40 is used to start a concealed range (CDY), 0x4F is used to terminate it (SCD).[1]: AppB.3.2.7
GRB, Green Background.
MSG, Mosaic Green. Switch to mosaic, green foreground.
(EDC2, not used)
0x93
ESC 0x53 (S)
(not used)
YLB, Yellow Background.
MSY, Mosaic Yellow. Switch to mosaic, yellow foreground.
(EDC3, not used)
0x94
ESC 0x54 (T)
(not used)
BLB, Blue Background.
MSB, Mosaic Blue. Switch to mosaic, blue foreground.
(EDC4, not used)
0x95
ESC 0x55 (U)
P-MACRO, Photo Macro. Followed by a single-byte parameter (0x40 for define, 0x41 for define and execute, 0x42 to define a transmit-macro, 0x4F to delimit the end of a macro definition).[1]: AppB.3.2.9 Second single-byte parameter (from 0x20 to 0x7F) identifies the photo macro being defined (from PM0 to PM95).
MGB, Magenta Background.
MSM, Mosaic Magenta. Switch to mosaic, magenta foreground.
WWON, Word Wrap On.
0x96
ESC 0x56 (V)
(not used)
CNB, Cyan Background.
MSC, Mosaic Cyan. Switch to mosaic, cyan foreground.
WWOF, Word Wrap Off.
0x97
ESC 0x57 (W)
(not used)
WHB, White Background.
MSW, Mosaic White. Switch to mosaic, white foreground.
SCON, Scroll On. Next-lining off the bottom of the screen moves the rest of the screen up to make space.
0x98
ESC 0x58 (X)
RPC, Repeat Control. Repeats preceding spacing graphical character a number of times specified by the low six bits of the following byte (from 0x40 to 0x7F). Repeats to end of line if byte is 0x40. Compare REP from Data Syntax 3.
CDY, Conceal Display. Display characters as spaces (might be terminated by SCD).
SCOF, Scroll Off. Next-lining off the bottom of the screen wraps around to the top of the screen.
0x99
ESC 0x59 (Y)
SPL, Stop Lining. Terminates underlining. For mosaic characters, non-underlined font corresponds to contiguous display, with the blocks within a mosaic character joined together.
USTA, Underline Start. Begins underlined letters, and switches to separated display for mosaics.
0x9A
ESC 0x5A (Z)
STL, Start Lining. Begins underlined letters. For mosaics, this corresponds to separated display, with the blocks within a mosaic character shown separated.
USTO, Underline Stop. Terminates underlining, and switches to contiguous display for mosaics.
^See Table C.9 in Annex C part 1 of T.101.[1] Caveat: the table itself is displayed in the PDF with severe mojibake (hence why the displayed table does not appear to correspond to the associated notes), and is supposed to look like ISO-IR-70[5] (besides the additional highlighted umlaut code).