2.4.2 System Controller
126.96.36.199 System controller components
a) ASIC (IC1)
The ASIC of this printer integrates conventional image processing ASIC and CPU on a single chip. The function of the image processing unit and the CPU
are described below.
Image processing unit
The image processing ASIC converts the RGB multi-value image data and YMCK multi-value image data from the host computer received after passing
through the interface connectors to six-color binary image data. In addition, the image processing ASIC has the following functions.
1) Engine controller communication control
This function controls serial and parallel communication with the engine controller.
2) Operation panel control
This function controls serial communication with the operation panel.
The 64-bits internal bus CPU runs in synchronization with the 264MHz internal clock. The internal clock is generated within the ASIC using the 132MHz
external clock input from a clock generator.
The CPU is connected to one 64MB DIMM board, one 4MB ROM chips, and one 8KB EEPROM chip. The CPU has the following functions.
1) DMA controller
The DMA controller manages the USB, expansion card slots, and other input interfaces and DMA transfer of the data stored in the DDR-SDRAM.
2) Interrupt controller
The interrupt controller receives and processes external interrupts from USB, image processing unit, and expansion card slots, in addition to the internal
3) Power supply on/off control
This function performs on/off control of the drive power (26.5 V, 5.1 V, and 3.3 V) supplied from the power supply based on the power button push-down
The 64MB DIMM is connected to the 64-bit data bus and is used as the work area.
The DIMM is used as the image buffer when print data is received.
c) FLASH ROM (IC3)
The 4MB FLASH ROM is connected to the 8-bit data bus and stores the printer control program.
d) EEPROM (IC10)
The 8KB EEPROM stores the setting values and adjustment values from the Main Menu.
e) 1.5V regulator IC (IC32)
This regulator IC generates the ASIC internal driving power supply (1.5 V).
f) 2.5V regulator IC (IC31)
This regulator IC generates the ASIC internal driving and DDR-SDRAM power supply (2.5V).
g) 1.25V regulator IC (IC4)
This regulator IC generates the termination power supply and reference power supply (1.25V).