HP Color LaserJet 5500 Technical Reference Manual page 244

Printer-Specific Job
Boundaries
A-32 Feature Support
LaserJet 4 Plus, 4M Plus, 4V, and 4MV printers. For
HP LaserJet 4Si/4SiMx and 5Si/5SiMx printers, resource
saving is only configurable from the control panel.
Printers that support PJL job boundaries:
HP LaserJet 4, 4M, 4 Plus, 4M Plus, 4V, 4MV, 4Si,
4SiMx, 4ML, 4P, 4MP, 4PJ, 4LJ Pro, 4LC, 4000 series,
5, 5M, 5P, 5MP, 6P, 6MP, 5Si, 5SiMx, 5Si Mopier,
HP Color LaserJet, HP Color LaserJet 5, 5M
The printers listed above handle the following conditions as
PJL job boundaries. When any of these conditions occur, the
User Default Environment values are loaded into the PJL
Current Environment, which then are loaded into the
Modified Print Environment.
Control panel reset
Printer language-specific exit command, such as ^D for
PostScript. (Printer language-specific exit commands are
not job boundaries when within a PJL JOB/EOJ
command pair.)
Data stream idle timeout (this occurs when a PJL job is in
progress and there is no data received over the I/O for a
specified length of time). To avoid a timeout, use the PJL
JOB or ENTER commands, since using the JOB or
ENTER commands increases the time the printer waits
for I/O data. This increase is because the printer is
processing a job with clearly indicated start-of-job and
end-of-job data stream commands. See the following
"Timeouts" section.
Using the control panel to perform a self test, or to print
a typeface list or demo page.
A job boundary indicated by the I/O card, such as the
AppleTalk end-of-file.