Canon LBP-860, Руководство по обслуживанию

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CHAPTER 2
b. Banding Coprocessor
The banding coprocessor is an Intel
8296 printer coprocessor that
integrates a graphics accelerator and
compression processor necessary for
complex page description language
controllers. provides all
necessary system control for the CPU to
interface to DC controller.
has following main functions:
KOM Control
Control
Video Interface
Communication Interface
Bus Interface support
The Generic Array Logic device
generates DRAM RAS control signals
under direction from the 82961KD.
DRAM
The contains two banks
of DRAM soldered on
board, and two DRAM SIMM
modules. Each SIMM module can
contain 1. 2. 4. 8. 16 or 32 MBytes of
The DRAM is used for storing
print data. video data, and
variable data used for program control.
d. ROM
Controller contains one bank of
Page Mode ROM and two KOM
SIMM modules. The Page Mode ROM
may be 2 or 4 MBytes. The two SIMM
modules may be from 1 to 16 MBytes.
ROM is used for storing the Controller’s
program and font data.
1.
e. EEPROM
The 2 serial EEPROM is provided
for non-volatile storage of the printing
environment, number of prints, and so
on.
f. Serial Controller
The Serial Controller is used
as the interface to the Host serial
port for printer data.
serves as the connector for this
interface.
Parallel Port Interface
A 256 byte FIFO is used to buffer
printer data from the Host parallel port.
serves as the connector for the
parallel port interface. The Generic
Array Logic device controls the
transfer of printer data over the Host
parallel port.
Engine Interface
The engine interface, both signal
generation and print engine communi-
cation. is controlled by the 82961KD
device.
Video Logic
Logic is provided to select the video
clock frequency supplied to the
82961
8X PLL Selections are,
59.64024 clock for 600 600
resolution. 14.910506 MHz clock for
300 300 resolution, or an external 1X
clock for 1200 1200 resolution.
External Video
The connector J 140 is provided to
support video post processing features
such as resolution enhancement or
resolution doubling. In addition, it can
be used to provide clocks not provided
by controller, supporting non standard
print engine resolutions.
The external I/O Slot (connector 5172)
supports user installed Host I/O
controllers such as AppleTalk and
Ethernet. An
connector is used
to interface to the processor
LAD bus. In addition, this connector
provides for the addition of a video
adapter interface that allows for
superimposed video on the existing
video data supplied by the