Canon BJ-W9000, Руководство по обслуживанию

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g) The system controller sends the image data contained in the output buffer to the
band memory in the head controller. This occurs when the image data request
signal is issued by the head controller upon the completion of the current scan (the
horizontal travel of the carriage). This data transfer is completed within the time of
the next scan/current scan and so finishes before the start of the following one. The
amount of image data transferred is equivalent to a size that corresponds to a single
paper feeding and meets the currently specified print quality. The head controller
splits the received data into groups by color and stores them in the band memory.
The band memory is able to contain the image data that matches two bands (that is,
the region defined by a maximum paper width of 43 in. x 256 nozzles x two passes)
for each color.
h) To produce the optimal image data for the printer, the head controller processes the
data stored in the band memory in the following order:
1) Allocates the data to left heads and right heads uniformly to produce consistent
print output.
2) While expanding the data such that they will be printed with the number of
passes defined by the print quality setting, stores those data in GA1, 2 and 3 of
the head controller.
3) Creates optimal image data based on the mask pattern data located in the SRAM.
i) The head controller sends the optimized image data to the GA in the carriage
controller timed to synchronize with the speed of the carriage (the speed required
for 1200dpi output).
j) The carriage controller converts the optimized image data received from the head
controller so that they support the configuration information of each BJ print head
and the temperature of the printer. The controller stores the image data in the
output buffer in the carriage controller GA, and then sends the data to the BJ print
heads in the form of print signals.
The carriage controller GA sends to the BJ print heads the block enable signal,
which allows mask processing. This is achieved by selecting the driving block for
each nozzle so as to implement the optimal head driving.
k) The BJ print heads internally convert the received print signals, which are in serial
format, into the parallel data used by a single nozzle array for printing. Then the
print heads combine the parallel data with the block enable signals using the AND
logic operation to perform printing.
l) The CPU in the system controller controls print signals while communicating with
the carriage controller, the CPU of the motor controller, and the mech. controller. It
therefore manages the overall printing operations by controlling the mechanical
driving system and checking the state of the driving system.
Part 4: Technical Reference BJ-W9000
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