Introduction
MOTOROLA
MC68322 USER’S MANUAL
1-11
1.4.5 Duplex Printing
The MC68322 supports duplex printing applications. Duplex printing is the operation of
placing an image on both sides of a page before it leaves the printer. In a duplex laser
printer, paper travels out of the input hopper and under a drum to receive a toner image. The
paper then travels through a fuser to set the toner onto the first side of the paper and into an
internal duplex hopper. Next, the paper moves out of the duplex hopper and under the drum
again to receive the second toner image, this time on the reverse side of the paper. Finally,
once the second image has been fused, the paper is placed in the output hopper.
Figure 1-8. Duplex Laser Printer Paper Path
Since the image is placed on both sides of the page in duplex printing, image orientation is
important. When the page is turned to read either side, both images must appear right-side
up. To achieve the correct image orientation, the physical characteristics of the print engine
and the format of the printed page must be taken into consideration. For example, it is
important to know how the page is turned over to expose both sides to the drum inside the
print engine as well as how the page is going to be bound in the completed document.
Images printed on the opposite side of a page may have to be rotated 180
°. Understandably,
these types of pages are called 180
° pages. They require pixel data to be transmitted from
the page image bitmap starting at the bottom-right corner and then continuing from right to
left, bottom to top. Pages that do not require this type of rotation are called 0 pages and
they are transmitted starting at the top-left corner and then continuing from left to right, top
to bottom.
In banding applications, 180
° pages require special attention. Since the page image is
transmitted to the print engine in bottom to top order, bands must be generated in this order
too. The MC68322 directly supports 180
° page rendering and printing as required by duplex
banding applications. The RGP and graphic order instruction set are specifically designed
to render images either top to bottom or bottom to top, thus enabling banding of both 0
° and
180
° pages on duplex printers.
DRUM
PAPER DIRECTION
INPUT
HOPPER
DUPLEX
HOPPER
(INTERNAL)
OUTPUT
HOPPER
FUSER
DOUBLE SIDED PAPER PATH
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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