Lexmark T630 User's Reference Manual page 253

PCL SmartSwitch
Purpose:
To configure the printer so it automatically switches to PCL emulation when a print job received
through the network port requires it, regardless of the default printer language.
Values:
On* Printer examines data on the network interface and selects PCL emulation if the
data indicates that is the required printer language.
Off Printer does not examine the incoming data. The printer uses PostScript emulation
to process the job if PS SmartSwitch is On, or uses the default printer language
specified in the Setup Menu if PS SmartSwitch is Off.
See also:
PS SmartSwitch;
PS SmartSwitch
Purpose:
To configure the printer so it automatically switches to PostScript emulation when a print job received
through the network port requires it, regardless of the default printer language.
Values:
On* Printer examines data on the network interface connection and selects
PostScript emulation if the data indicates that is the required printer language.
Off Printer does not examine the incoming data. The printer uses PCL emulation to
process the job if PCL SmartSwitch is On, or uses the default printer language
specified in the Setup Menu if PCL SmartSwitch is Off.
See also:
PCL SmartSwitch;
NPA Mode
Purpose:
To specify whether the printer performs the special processing required for bidirectional
communication, following the conventions defined in the Network Printing Alliance (NPA) Protocol.
Using the printer menus
Printer Language
Printer Language
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