Factory Defaults; Default; Current User Job Environment; Modified User Job Environment - Xerox 850DP - Phaser Color Solid Ink Printer Manual

Version 10.0
AccXES PJL Interface
The AccXES architecture will maintain four levels of environments in a manner very analogous to the
HP-PJL implementation. An environment is the collection of all user selectable parameters in use at a
certain time. The Printer State class of variables are not included in this environment classification.
They are maintained separately. The four environments supported are discussed below.

5.1.3.1 Factory Defaults

This environment corresponds to the Factory Default environment in standard HP-PJL. It is stored
permanently in printer ROM. The settings cannot be modified.

5.1.3.2 Default

This environment corresponds to the User Default environment in HP-PJL. It is stored in a non-volatile
manner in printer NVRAM, if such exists. The User Default environment takes on the settings
contained in the Factory Default environment when the printer leaves the factory, and when the
printer receives a valid INITIALIZE HP-PJL command. The printer's User Default settable variables
are modified through the printer front panel interface, or through the HP-PJL DEFAULT command.
Some variables are read only, and may never be modified.
Note: If parameters are modified using the HP-PJL DEFAULT command the user should wait a
minimum of 30 seconds before powering off the printer to allow time for the printer to update its
NVRAM. Failure to wait for this period may result in the loss of the modified parameters after the
printer is powered on.

5.1.3.3 Current User Job Environment

This environment corresponds to the PJL Current environment in HP-PJL. It takes a snapshot of the
values of the User Default Environment on the reception of a new user job or a HP-PJL reset condition
such as an @PJL RESET command or a UEL sequence. Only four groups of parameters are stored in a
job: the Printer Group, and the Emulation Group, under the Printer Class, and the Job Processing
Group and Page Processing Group under the Processing Class. Other parameter groups are "read-only"
in the Current User Job Environment and will take on their corresponding values in the User Default
Environment.
The reason for this disparity is straightforward. These parameter groups may be particular to each
individual job and have to be manipulated as such. They need a separate environment beyond the User
Default Environment. This is especially true since there may be many jobs simultaneously in the
system at one time.
On the other hand, the other parameter classes affect the physical printer as a whole, and are not tied
to any one job. Further, there are many ports over which commands to change these variables may be
received simultaneously. Centralizing these parameter classes into the User Defaults environment
simplifies implementation by creating a single, lockable parameter resource, eliminates race conditions,
and eliminates the complexity of maintaining multiple data bases holding the same data.
These settings in the Printer, Emulation, Job and Page Processing Groups are modifiable through the
PJL SET command. They override the User Default features until the next PJL reset condition. The
PJL INQUIRE command will report back to the client host the settings of the variables at the time of
the start of the job or the last PJL reset. If the value of a variable (such as INROLL1STAT) is changed
by some other agent after the PJL job started, the INQUIRE will not see this change until the next PJL
job or the next PJL reset.

5.1.3.4 Modified User Job Environment

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