HP PCL/PJL reference - Printer Job Language Technical Reference Manual

5-4 Job Separation Commands EN
• DISPLAY="display text " — The command option DISPLAY
is used to display a job message on the control panel display.
The message is displayed when the printer begins to work on
this job and is removed when the last page of this job reaches
the output bin. The variable "display text" can be any
combination of printable characters and spaces or horizontal
tabs, with a maximum of 80 characters. The actual number of
characters displayed depends on the printer. The display limit
can be determined by sending an INFO CONFIG command to
the printer. The printer will return DISPLAY LINES = value and
DISPLAY CHARACTER SIZE = value as part of the response.
Note For HP LaserJet 4PJ, 4V, 4MV, 5Si, 5SiMx, 5Si Mopier printers, if the
LANG variable is set to Japanese, messages are displayed using the
JIS X0201-76 character set.
For the LaserJet 4000, 5000, 8000, and 8100 series printers, if LANG
is set to POLISH, CZECH, or HUNGARIAN, messages are displayed
using the Latin 2 (ISO 8859/2) character set. If LANG is RUSSIAN,
messages are displayed using Cyrillic (ISO 8859/5). For
LANG=TURKISH, the display is in Latin 5 (ISO 8859/9). This is also
true for the HP Color LaserJet 4500 printer, except there is no support
for Turkish or Hungarian on this printer.
Comments:
When a JOB command is received, the printer does not recognize the
UEL command as a PJL job boundary until an EOJ command is
received. UEL commands within a PJL JOB/EOJ command pair are
treated as printer language resets; they default the print environment
to the PJL Current Environment settings, instead of the User Default
Environment.
If your application has status readback capabilities, you can monitor
the job status using the USTATUS command with the JOB option. If
job status is enabled and the printer receives a JOB command, it
returns a job status message.
Note Resetting the page count associated with unsolicited page status
affects only future pages. Pages already processed, but not yet
printed, are not affected.