Canon BJ-W3000, Руководство по обслуживанию

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CHAPTER 2. BASIC OPERATION
2–11
[7] Gate array (U208)
Provided with an 8-bit parallel input port
for the image data from the image
controller. Processes the image data
before sending it to the gate array
(U212). Also processes the internal print
data.
[8] Gate array (U212)
• Image data transfer control for the
image controller
• Conversion of image data
• Input ports for sensors, switchs, etc.
• Carriage position control using the
linear encoder
• Media sensor lamp signal output
• Solenoid output port
• Purge motor control
[9] Gate array (U204)
Operated by a clock from the CPU
(U221). Generates head drive pulse
signals.
[10] Paper feed motor driver (U233)
Generates paper feed motor drive signal.
[11] Carriage motor driver (U232)
Generates carriage motor drive signal.
[12] Purge motor driver (U234)
Generates purge motor drive signal.
Major functions of the ICs on the engine
controller are as follows.
[1] CPU (U221)
Connected to the DRAM (U216),
FLASH ROM (U219), EEPROM (U218)
and gate array (U204, U212) via the
address bus and data bus.
Run by the 16MHz external clock.
Major functions are as follows.
• Command communication with the
image controller
• Fan motor output port
[2] Sub-CPU (U202)
Connected to the CPU (U221). Major
function is to control the paper feed
motor and carriage motor.
[3] DRAM (U216)
2-Mbyte work area used to store tempo-
rary CPU data.
[4] FLASH ROM (U219)
500-Kbyte ROM containing the control
program.
[5] EEPROM (U218)
8-Kbyte ROM used to store timer suc-
tion, dot count, waste ink count and other
data.
[6] Reset IC (U227)
Detects the voltage supplied to the engine
controller at power ON or power
interruption, and resets the CPU (U221).