HP PCL/PJL reference - PCL 5 Comparison Guide

ENWW Printer-Specific Differences 2-89
Negative Motion Command
The Negative Motion command specifies whether negative motion
will be used, thus determining whether the full page must be buffered
before printing can begin.
?&a#N
If the page contains no negative motion, using the
?&a1N command
increases print speed.
Negative motion includes:
• Vertical motion toward the top of the page
• HP-GL/2 operations
• Print directions other than 0 degrees
• Landscape text
• When the top of the character cell on the next line is above the
top of the character cell on the current line
The default value of 0 delays printing until all the processing of input
data for a page is complete. This is for software that needs to
compose the data before printing.
A value of 1 allows data to be printed as received, rather than first
stored in a buffer. Otherwise, printing will be delayed until all
processing of input data is complete.
Note This command must be sent before any printable data is received by
the printer.
# = 0 - Picture contains negative motion (page formatting
printers)
1 - Picture contains no negative motion (swath printers)
Default =0
Range =0, 1