Printing Basic Bar Codes
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The Bar Code Control Character
Except for a few ASCII control characters supported by bar code mode, all bar code sequences are
introduced by the “bar code control character”. The “bar code control character” is the printable
ASCII caret character “^” (94 decimal, 5E hex).
Note in particular that the ESC control code (27 decimal, 1B hex) is not used in bar code mode. When
the caret character “^” is seen in this chapter, it does not mean ESC and it does not mean “control-_” !
Other Control Characters
BEL is processed and causes the printer to ring the bell. This is supported so that you may annoy the
printer operator without exiting bar code mode.
ETX is processed so that ETX/ACK software handshake will work in bar code mode. (As an aside,
XON/XOFF software handshake will also work in bar code mode. However, XON/XOFF characters
are transmitted only from the printer to the host; XON/XOFF characters should not be sent to the
printer.)
FF is supported so that you may easily reach top of form without exiting bar code mode.
LF advances the paper to the next line feed boundary at the currently selected line pitch. If already
positioned at a line feed boundary, this will peform a full line feed, if not a partial line feed will be
performed to position the paper at the next line. This allows the paper to be positioned properly for
text printing after bar code mode is exited.
All other control characters are ignored in bar code mode.
