Canon iPF700, Руководство по обслуживанию

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Chapter 2
2-28
2.4.2 Main Controller
2.4.2.1 Main controller components
0013-8235
F-2-22
a) ASIC (IC2)
The ASIC with a 16-bit internal bus is driven in sync with the 66 MHz external clock. It supports the following
functions:
Image processing unit
This unit converts the RGB multi-bit image data or CMYK multi-bit data received from the host computer
through the interface connector to the binary image data for the ink colors used.
DMA controller
This controller controls the input interfaces such as the USB and expansion card slot as well as DMA transfer
of the data to be stored in the DIMM.
Image data generation/output function
This function generates image data for color printing from the received image data and the mask pattern
(corresponding to print mode) stored in the DIMM, and store the generated image data in another DIMM. It also
outputs the generated image data to the carriage relay PCB.
Interrupt controller
This controller receives and processes internal interrupts and external interrupts from the USB, image
processing unit, and expansion card slot.
Timer function
Even when the printer is turned off, the timer function is held on using the RTC and secondary lithium battery
to assist the cleaning function.
When the power cord is plugged to the outlet, power is supplied to the RTC and therefore the secondary lithium
battery power is not consumed.
Heat Enable signal control function
This function uses the pulse width to perform variable control of the time of application of the Heat Enable
signal to the nozzle heater for each nozzle array (PWM control).
Linear scale count function
This function reads the linear scale when the carriage moves, thus generating the ink jet timing. It also counts
the linear scale timing cycle using the reference clock to measure the carriage moving speed.
Dot count function
This function counts the fired dots used as the information for Heat Enable signal control, maintenance jet
control, cleaning control, and remaining ink level for each nozzle array.
Operation panel control function
This function controls serial communication with the operation panel.
IC604
IC603
IC602
IC601
IC2 IC701 IC3100 IC802
IC2900
IC2902
IC2802
IC3203