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Graphics Pass
A Graphics Pass begins with a Pass Start (^M, ^U, ^V, or ^E) and ends with a Graphics Pass Terminator
(Pass Start, CR, LF, FF, ^-, or ^,). Any characters placed between the Pass Start and Pass Terminator
will print as block characters. Also, all GPL Graphics Image commands, such as the Bar Code and Line
Drawing commands must be sent within a Graphics Pass. Each Graphics Pass is treated by the printer as
a set of data and instructions to be processed and printed, starting at the current paper position, before
accepting any further data from the host.
Each pass begins at the current vertical paper position and the left margin. From this point, the printer
prints to the right and down the page.
NOTE: It is not possible to print above the starting point of a Graphics Pass.
It is possible, however, to issue positioning commands within the pass which position the paper at
any point below the start of the pass.
NOTE: When (LF, FF, ^*, ^,) are used to terminate a Graphics Pass, they lose their normal meanings,
and become Pass Terminators such as
^-. When used outside the Graphics Pass they take on their normal meaning.
Not all GPL commands and data sent to the printer need to be in a pass. In fact, many commands must
be outside of a pass to function properly. For instance, the command ^H sets the form length if it is used
outside of a pass, but sets the pass height if it is used within a Pass.
At this point, it may seem difficult to decide when to use a Graphics Pass. If there is any doubt about
whether a command should go inside or outside of a pass, refer to Appendix E, “Command Table” on
page 231. The GPL commands fall into two general categories:
Inside A Pass
• GPL positioning commands (e.g., tabs, vertical justification, etc.)
• GPL printing commands (e.g., barcodes, lines, boxes, certain fonts, etc.)
• Block characters
Outside A Pass
Global Graphics Pass commands (i.e. commands which act on the entire pass as a unit, such as those
which cause the entire Pass to be repeated or stored in memory for later use).
Environmental commands such as form length setting, Graphics Mode, and Free Format.
Non-GPL Data
Any data you want to go to the current Control Panel emulation must be sent outside of a Graphics Pass.
Appendix E, “Command Table” on 231 lists all GPL commands.
Pass Spacing (Modplot)
Code V output can be affected by a Plot Mode option that is available on your printer. Appendix F,
“Modplot” on 235 explains the Modplot option and how it affects Code V output.
Pass Buffer Length
Data received from the host is stored in a Pass Buffer. The Printer begins to process a Graphics Pass
when it receives a Pass Terminator. The printer processes one pass at a time, printing at the end of each
pass. If the Pass Buffer fills up before the printer encounters a Pass Terminator, it terminates the pass
and attempts to process and print it.