HP 4 FAMILY - Manual (Page 122)

Updated Features Printers with a “B” or “C” revision code, indicated by the
third digit in the serial number, have the following
additional new features. (Print the self-test to see the serial
number.)
Two-Byte Fonts. Provides support for two-byte (large)
fonts with more than 256 characters. Two-byte fonts
support such large symbol set mappings as Unicode,
Shift-JIS, JIS208, and Big5. Two-byte fonts are
compatible with current PCL data structures.
Frame Buffer/MEt Architecture. Provides MEt
(Memory Enhancement technology), which overcomes
memory contention problems. Drivers can use the PJL
SET command (@PJL SET PAGEPROTECT=LETTER/
LEGAL/ A4/OFF) to put the printer into a page protect
mode that reserves the memory equivalent of a complete
full-color frame buffer for the current page size. Page
protect mode reserves printer memory blocks large
enough to represent cyan, magenta, and yellow (CMY)
bitmaps for an entire page of the currently selected
media).
Noise Dither. Two new halftone render algorithms
(noise dither and monochrome noise dither) have been
added.
Arbitrary Dither Matrix Sizes. The printer now
allows the full 16-bit range for downloaded dither matrix
height and width (?*m#W).
2-86 Printer-Specific Differences