HP 4 FAMILY - Manual (Page 11)

PCL Feature
Support
Table 1-1, the PCL Feature Support Matrix, lists all the
printer commands from the PCL 5 Printer Language
Technical Reference Manual and identifies which of these
commands are supported by the various printers. More
detailed PCL information for each PCL 5 printer is
provided in Chapter 2.
Note The PCL 5 Printer Language Technical Reference Manual
(part number 5961-0509) was revised for the release of the
HP LaserJet 4 printer and contains all PCL language
features up to the HP LaserJet 4 printer.
With the introduction of the HP LaserJet 4 printer,
Hewlett-Packard enhanced the PCL 5 printer language to
provide some new features. The major improvements to the
PCL 5 printer language are listed below.
600 dpi support for higher quality printing
45 scalable typefaces for greater type variety
TrueType rasterizer (in addition to the Intellifont
rasterizer) for fast Windows printing, and for matching
Windows and printer type (easy WYSIWYG)
New graphics commands for faster and better curves and
shading quality
Bi-directional I/O for easier use and sharing by providing
printer status to computer applications
Automatic and faster printer language switching
Automatic I/O switching for faster I/O rates
Improved memory management so most pages print in
standard memory
Improved PCL and HP-GL/2 performance for faster
graphics and text printing
Feature Set 1-3