2.4.3 Engine Controller
220.127.116.11 Engine controller components
a) CPU (IC511)
The CPU, with a 32-bit internal bus, operates in synchronization with the 132-MHz internal clock that is generated from a 66-MHz external clock.
The CPU is used 8-MB SDRAM (IC508), 8-MB FLASH MEMORY (IC503) and 32-KB EEPROM (IC704). The CPU performs parameter control and
has the following functions.
This function is used for the cleaning functions.
The internal RTC (IC725) and lithium battery (BAT501) allow the timer to operate even when the AC power supply is off for performing the cleaning
EEPROM control function
In addition to the EEPROM (IC704) with on-board, it controls the six color independent ink tank EEPROM, maintenance cartridge EEPROM, and head
Ink tank level detection
This function detects the remaining ink level for each color based on the signals from the electrodes mounted on the hollow needle.
This function performs I/O control from the sensors.
b) ASIC (IC512)
The ASIC, with a 32-bit internal bus, operates in synchronization with the 100-MHz internal clock that is generated from a 50-MHz external clock.
It uses two 32MB SDRAMs and two 8MB SDRAMs having the following functions:
System controller communication control
This function controls communication with the system controller.
Image data reception
This function receives the image data from the system controller and stores it in the SDRAM (IC501, IC502).
Image data generation/output
This function generates the image data for printing each color from the image data received from the system controller and mask pattern corresponding to
the print mode in the SDRAM (IC501, IC502) and stores it in SDRAM (IC506, IC507).
This function also controls the output of the generated image data to the carriage relay PCB.
Heat enable signal control
This functions uses the pulse width to perform variable control of the time that the heat enable signal is applied to the nozzle heater board for each nozzle
array in the printhead.
Linear scale count
This function reads the linear scale when driving the carriage, divides the 150lpi timing signal by eight to generate the 1200lpi timing signal. It also counts
the linear scale timing cycle using the reference clock to measure the carriage driving speed.
This function counts the discharge dots used as information for the heat enable signal function, maintenance jet control, cleaning function, and remaining
ink level for each nozzle array.
This function performs driving control of the carriage motor, and suction fan and temperature control of the printhead based on the control signals from
Feed motor control
This function controls the feed motor speed and position based on the control signals from the CPU.
This function performs I/O control from the sensors and controls the driving units of the motors, clutch, solenoids, and other parts.
c) Driver ASIC (IC705, IC706)
The image data generated by the ASIC (IC512) undergoes differential processing to reduce noise and then is sent to the carriage relay PCB.
d) SDRAM (IC508)
IC502 IC501 IC512 IC705 IC706 IC703 IC709
IC728 IC729 IC727 IC702