Ithaca Epic 950, Руководство по интеграции

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Programming for the Epic 950 Epic 950 OEM Integration Manual
Page 62
Rev G
95-05245
Text Objects
A text object is simply a line of printable characters. A text object is created whenever
the Epic 950 receives a printable character that is not otherwise part of a command.
Once it is created, a text object will remain active until it is terminated.
While a text object is active, any printable characters sent to the Epic 950 will be added
to that text object. The only exceptions are printable characters that are sent as part of a
command. While a text object is active, commands that alter text line attributes (such as
font and double-high character commands) are ignored. Commands that alter text
character attributes (such as double-wide and inverse) may be sent at any time, though.
Line attributes include the five basic fonts (P, M, U, and T), plus the double-high font
command (
GS DC2 ). These commands may not be issued while a text object is active;
instead they should be issued before a text object is begun. The font line attribute
persists until another font command is received. The double-high line attribute persists
either until the cancel double-high command (
GS DC3 ) is sent or the current font is
changed. The character attribute commands include the set font to double wide ( SO )
and set inverse print mode ( GS RS ) commands. These commands may be issued or
canceled at any time. Character attributes persist only until the end of a text object.
A text object can be terminated with a carriage return, a line feed, or both, in either
combination. If the length of the text object exceeds the space allowed for printing, it will
either wrap to the next line or truncate at the end of the printable area. The decision to
wrap or truncate is determined by the select line wrap/truncate mode command (GS T).
By default, text objects will wrap to the next line.