Videotex character set

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.

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.

[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.

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.

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.

In addition to sets of graphical characters and control characters , some Videotex formats included Picture Description Instructions (PDI) sets used for in-band vector graphics .