HP LaserJet 4000 Printer series - Introduction

background image


In some situations, the amount of available memory for printing pages
may be smaller than that required for printing. To make more effective
use of the available printer memory, newer HP PCL 5 printers
incorporate new methods for managing memory. This smaller amount
of available memory is made more usable by:

• Memory Enhancement technology, MEt, (available on all

HP LaserJet 6, LaserJet 5, and LaserJet 4 family printers
except the 4, 4M, 4Si and 4SiMx)

• Adaptive Data Compression, ADC, (available on

HP LaserJet 4, 4M, 4Si, 4SiMx and DeskJet 1200C printers)

• Following recommended practices for transmitting data,

especially raster graphics, to the printer

• For the HP LaserJet 4L, using Raster Graphics Adaptive

Compression (PCL compression mode five)

All HP LaserJet 4, 5 and 6 family printers have internal programming
for optimizing the use of limited memory. HP LaserJet 4, 4M, 4Si,
4SiMx, and DeskJet 1200C printers compress raster graphics data
using a system called Adaptive Data Compression or ADC. The other
HP LaserJet 4 / 5 / 6 printers use MEt to compress not only raster
graphics data, but also to compress fonts, improve memory usage for
page protection, and provide an overall improvement in memory
efficiency. Both systems operate automatically and without any
intervention from the user.

The HP Color LaserJet printer has memory management features
similar to MEt, but has additional features for color processing.


For information about products newer than those included in this
book, see the PCL5 Comparison Guide Addendum, which includes
product-specific information about newer products, as well as
commands and variables added to support these newer products.

background image

5-2 Memory Usage