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Chapter 1 Graphics Processing Language
Graphics Processing Language
The Graphics Processing Language (GPL) consists of a set o f commands
that are used to print graphics images such as block char acters, barcodes,
lines, and boxes, as well as provide formatting control for the correct
placement of these images. Relatively complex image s may be created
through the use of a few simple commands.
The original version of QMS Code V (version 1) differs slightly from the
current version (version 2). The primary difference between the two is in the
way vertical justification commands are implemente d. Specifically, version 1
used an approximation for 0.1 inch that has been made mor e precise in
version 2. If you are running an application designed for version 1, the printer
can be switched to a mode that can emulate it.
Graphics Mode
For the printer to recognize GPL commands, it must fir st be placed in
Graphics Mode. When the printer is in Graphics Mode, the printer scans the
data received from the host for GPL commands, passing non-G raphics data
to the current emulation. When the printer is not in Graphi cs Mode, Code V is
disabled and will not search the incoming data for GPL commands.
Graphics Mode may be entered while the printer is in any emulation. G raphics
Mode should not be entered while the printer is in Plot Mode. The printed
output of Code V adheres to all the applicable Control Panel settings (such as
LPI, CPI, Form Length, etc.).
NOTE: All escape sequences in this manual are in ASCII notation.

Turning Graphics Mode On

Graphics Mode is turned on with command ^PY, which must begin in the fir st
column of a line, followed by one of the following six terminators.
1. ^- (caret hy phen)
2. ^* (caret a sterisk)
3. ^, (caret c omma)
4. Carriage Re turn
5. Line Fe ed
6. Form Feed
Once the printer is in Graphics Mode, the data it receives is read into a Pass
buffer. The printer will stop looking for characters from the h ost and process
the data held in this buffer when one of the terminators is rec eived. If the
buffer fills up before receiving a Pass Terminator, data in the buffer will be
processed and printed before the printer accepts any more c haracters.