Xerox WorkCentre Pro 412, Service Manual

Page: 27 / 192

Circuit Description
WorkCentre Pro 412
Launch Issue 5-1
August 2001
5. Circuit Description
5-1 Main PBA
5-1-1 Summary
The main circuit that consists of CPU, MFP controller (built-in 32bit RISC processor core: ARM7TDMI) includ-
ing various I/O device drivers, system memory, scanner, printer, motor driver, PC I/F, and FAX transceiver
controls the whole system. The entire structure of the main circuit is as follows:
OSC
20 MHz
POWER
ON RESET
MODEM
CIP3
OSC.(Video)
45.3928 MHz
LIU
OSC.
48 MHz
USB
INTERFACE IC
(UNICON)
USB
RTC
PARALLEL
INTERFACE
OPE PANEL
INTERFACE
PROGRAM
ROM
1MB x 4EA
SRAM
256K
DATA RAM
(DRAM)
8MB x 2EA
PLL
Reset & WDT
Generation
ARM7TDMI
Cache 8KB
ROM/SRAM/
FLASH ROM
Control
(4 Bank)
I/O
Control
(5 Bank)
CPU BUS
Interface Block
GPIO
SYSTEM BUS
Interface Block
[Arbiter]
VIS
ADC
RAM : 512B
UART
(3 CH)
Interrupt
Control
(4 External)
Timer
(3 CH)
Tone
Generator
Engine
Comm. I/F
JBIG
LRAM:1296B
CXRAM:256B
RAM
512B+512B
HPVC
HCT
DMAC
(2 CH)
PPI
PVC
GEU
EDO/FPM
DRAM
Control
(4 Bank)
MA
MD
RAS
CAS
/CS,/RD,/WR
A/D BUS
IMCS
/MIR0,
/RD,/WR
D0~D7
A0~A4
RST_OUT
IOCS
/RST_OUT
/XDACK
/XDREQ
/SDIP CS
/RD,/WR
D0~D15
A0~A5
Block Diagram