HP PCL/PJL reference (PCL 5 Printer Language) - Technical Reference Manual Part II

24-10 Programming Hints EN
Performance
PCL Commands
Since PCL printers are command driven devices and each command
takes a finite amount of time to process, pages composed of a large
number of commands may not print at maximum speed. Most
commands can be used frequently on a page without adversely
affecting the printer’s performance; however, certain commands take
more time to process and therefore, if used frequently on a page,
may decrease printer performance. An excessive number of font
selections per page (selection using font characteristic commands
or selection by ID number) may decrease printer performance.
Print Data
There is a limit on the amount of data, as well as the number of
commands, that the printer can process per page at maximum speed.
Print Overrun
As data is received by the printer, it is processed and stored in an
intermediate format. The intermediate data is later processed and
printed. During the physical printing of a page, the page moves
through the printer at a constant speed. Thus, some pages cannot
be printed because the page’s intermediate data cannot be
processed fast enough to keep up with the physical speed of the
page as it moves through the printer. When this condition occurs,
an error number ‘‘21’’ (
ERROR 21 - print overrun) is displayed on
the printer’s control panel. A page causing this error can be printed by
setting the printer’s page protection feature to ON (see next section).
Page Protection
If enabled, page protection reserves an amount of memory for the
page image process, allowing the printer to create the entire page
image (in memory) before physically moving the paper through the
printer.