User`s manual

8–46 IBM Proprinter Emulation
Overscoring
ASCII Code ESC _ n
Hex Code 1B 5F n
Dec Code 27 95 n
Purpose Enables or disables automatic overscoring of all characters.
Discussion When automatic overscore is enabled, all characters (including spaces
and spaces resulting from tabs) are overscored until disabled. Full–height
graphic characters are not printed with overscores.
An ESC _ code enables or disables automatic overscoring, as follows:
If n = odd, the overscore attribute is enabled and all printable characters
following (spaces included) are printed with an overscore.
If n = even, the overscore attribute is cancelled.
An ESC _ code can occur at any place in the datastream and is acted upon
immediately. All numerical parameters are in the 00 to FF hex range unless
stated otherwise. Unspecified parameters are ignored to the point where the
error is detected, then subsequent symbols are interpreted.
Use caution when combining this command with other print attributes:
arbitrary combinations might yield unexpected results.
Example The following sample program illustrates automatic overscoring and
overscoring reset.