Chapter 5: Pcl 5 Emulation: Lexmark; New Pcl 5 Commands To Support Bar Codes; Bar Code Descriptor Esc&X#W[Descriptor Data]; Transfer Bar Code Data Esc&Y#W[Bar Code Data] - Lexmark 6500e Technical Reference Manual

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PCL 5 emulation: Lexmark
This section discusses the Lexmark-specific commands implemented in the Forms and Bar Code
Card.

New PCL 5 commands to support bar codes

Support of new bar code functionality requires new Lexmark-unique PCL 5 definitions that provide
access to the new functionality. Two new commands are implemented, ESC &x#W and ESC
&y#W.
ESC
Bar code descriptor &x#W[descriptor data]
This escape sequence is used to describe what bar code to print and all other parameter settings
required to build the bar code. The first two bytes of this command designate the symbology. The
remaining bytes are then interpreted accordingly, based on the symbology. Each symbology has its
own defined descriptor header. The first two bytes are required. The remaining bytes are optional. If
those bytes are not sent, then the settings are set to appropriate defaults. The number of bytes of
descriptor data is indicated by #.
ESC
Transfer bar code data &y#W[bar code data]
This command is used to transfer a raw block of bar code data to be encoded according to the
specifications in the last valid bar code descriptor command received. If no valid descriptor is sent,
then this command is ignored and the data is flushed. The number of bytes of descriptor data is
indicated by #.

Compatibility safeguard

These commands, if sent to an HP printer, are flushed and nothing prints. A future HP PCL 5
enhancement could utilize the two escape sequences that have been chosen, forcing future Forms
and Bar Code Card PCL 5 emulations to honor the HP versions of these commands and to ignore
them in a bar code context. To avoid this conflict, use the PCL 5 Lexmark enhancement switch.
Setting this switch lets a future Forms and Bar Code Card PCL 5 emulation decide which way to
interpret the new escape sequences. The switch is a GL/2 command.
PCL 5 emulation: Lexmark
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