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

6-2 Environment Commands EN
Print Environments
At any time during printer operation, the printer's current feature
settings are referred to collectively as the print environment. When
certain printer events occur, such as the incidence of a printer
language reset, RESET command, or other PJL reset condition, the
print environment settings can default to the settings of other stored
environments.
The printer constantly maintains four environments, which are listed
below in priority order:
Factory Default Environment (lowest priority)
User Default Environment
PJL Current Environment
Modified Print Environment (highest priority)
The Factory Default Environment holds the initial feature values set at
the factory, which can be used for default values when a complete
reset is needed. The User Default Environment holds the settings
modified with the DEFAULT command, or set from the control panel.
The print environment defaults to the User Default values when
various printer conditions occur, such as the end of a PJL job, a PJL
reset condition, or when certain PJL commands are executed. The
PJL Current Environment contains the current PJL feature settings.
When a printer language is entered or a new job begins, the PJL
Current Environment settings are loaded into the Modified Print
Environment, providing a base feature set which the application can
modify if needed. After a printer language is entered, feature settings
are recorded in the Modified Print Environment.
Note HP LaserJet 4L, 5L, 6L, and 1100 series printers do not have
NVRAM. The PJL Default and Current Environment settings are
stored in RAM and are reset to the factory default values during a
power cycle.
Each environment is explained in more detail below:
Factory Default Environment — This environment consists
of a group of feature settings that are permanently stored in
the printer. The printer uses these settings when it is powered
on for the first time after leaving the factory, and after the
INITIALIZE command is received.