HP LaserJet 4 Plus and 4M Plus Printers
HP LaserJet 4 Plus and 4M Plus printers are performance-enhanced
follow-on products for HP LaserJet 4 and 4M printers, respectively.
The HP LaserJet 4M Plus printer is the multi-platform (PostScript)
version of the LaserJet 4 Plus printer.
In addition to extra speed, these printers also have the following
added features which are not controlled using PCL:
• Memory Enhancement technology (MEt), which uses
memory-saving techniques to better utilize available memory
(refer to Chapter 5, “Memory Usage” for additional
information). MEt is not controlled using PCL.
• Resource saving, as in the LaserJet 4Si printer. Resource
saving allows saving information for the current language (PCL
or PostScript) when switching to another language. If resource
saving is enabled, all the permanent fonts, macros, and
user-defined patterns plus other miscellaneous data is saved
in a reserved portion of printer memory. This data is stored
until the language is enabled again. When the language is
re-enabled, the stored data is made available for use.
Resource saving is enabled from the control panel or using
PJL—no PCL commands are required for this operation.
• EconoMode, a feature supported by HP LaserJet 4L and 4P
printers, allows the user to reduce the amount of toner used by
removing about 75% of the dots from the printed page.
EconoMode is selected using PJL or from the control panel—it
is not controlled using PCL.
• Powersave mode, which minimizes power consumption when
the printer is sitting idle. The amount of idle time required
before the printer goes into powersave mode is configurable
using the control panel or PJL.
PCL operation in these two printers is almost identical to that of
HP LaserJet 4 and 4M printers, except HP LaserJet 4 Plus and 4M
Plus printers support Logical Operations (ROP3) as explained in the
HP LaserJet 4ML printer section in this chapter. In addition, the
internal fonts in HP LaserJet Plus and 4M Plus printers support the
Latin 2 and Latin 5 symbol sets for all typefaces (in the HP LaserJet 4,
4M, 4Si, and 4SiMx, only 15 of the 35 Intellifont typefaces support
these symbol sets). Refer to Table 1-1, PCL Feature Support Matrix,
for the commands these printers support and to Chapter 3, “Internal
Typefaces/Fonts and Symbol Sets,” for font support information.
Printer-Specific Differences 2-61