Canon Color Bubble Jet BJC-1000 Series, Руководство по обслуживанию

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BJC-1000 Part 4: Technical Reference
Buffer controller
The buffer controller automatically reads the print buffer, and clears the data after it
is read.
Print head controller
The print head controller counts the number of dots of the bit map print data read
from the DRAM print buffer to control the heat pulse width (pre/main pulse width),
converts it to the COM and SEG signals for 8 x 8 matrix printing control, and
controls heating of the heater plate of the bubble jet nozzles of the BJ cartridge.
I/O port
Signals for the setting statuses determined by the RESUME button , head ID, paper
end sensor, home position sensor, pick-up roller sensor, head rank resistor,
thermistor, and head-driving voltage (VH) monitor are input through the input ports.
Signals for operations such as BJ cartridge detection and head-driving voltage
control are output from the output ports.
2) Control ROM (IC3)
The 8 M-bit control ROM contains the program for printer control.
3) DRAM (IC4)
Controlled by the printer controller, the 1 M-bit DRAM is used as print buffer and
working area.
4) Reset IC (IC7)
This IC detects the power voltage when power on or instantaneous power failure
occur and resets the MPU & Printer controller.
5) EEPROM (IC8)
Controlled by the printer controller, the 1 K-bit EEPROM (Electrically Erasable and
Programmable ROM) stores various function settings, the total count of printed
sheets, and the total waste ink amount.
6) Paper feed motor driver IC (IC6)
Controlled by the MPU & Printer controller, the paper feed motor driver drives the
paper feed motor (controlled by the two-phase exciter) with a constant-voltage
unipolar drive. The driver IC has four same circuits.
7) Carriage motor driver IC (IC12)
Controlled by the MPU & Printer controller, the carriage motor driver drives the
carriage motor (controlled by the one to two-phase exciter) with a fixed current
bipolar drive. In accordance with the switching signal from the MPU & Printer
controller, the peak current value is set to five steps and driven.
The driver IC has two same circuits.