Samsung SF4500, Руководство по обслуживанию

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6-2 Samsung Electronics
6-1-2 MFP Controller (KS32C6200 : U16)
M F P C o n t roller consists of CPU(ARM7TDMI RISC
p rocessor), 2K-byte cache, data and address buses,
serial communication part with LIU(Line Interface
Unit), OPE(OPERATION PANEL) print head con-
t ro l l e r, parallel port interface, external DMApart to
receive data from external color image pro c e s s o r
(SCANIP:U18), LF/CR motor diver
c o n t roller and I/O contro l l e r.
6-1-2-1. SYSTEM CLOCK
The internal clock frequency is 30MHz. 30MHz
system clock (MCLK) supplied from the outside is
used without being divided inside.
6-1-2-2. DATA & ADDRESS BUS CONTROL
• /RD & /WR
/RD & /WR signals are synchronized with
MCLK(30MHz) and become LOW ACTIVE.
These signals are strobe signals used to read and
write data when each CHIP SELECT is connected
with /RD and /WR pin of RAM, ROM, MODEM
and the outside devices and becomes active.
• C H I P SELECT (/IP_CS, /ROMCS, /MCS /
R A M C S )
- /IP-CS : SCANIP(U18) CHIP SELECT (LOW
A C T I V E )
- /ROMCS : ROM/FLASH MEMORY(U5) CHIP
SELECT (LOW A C T I V E )
- /MCS : MODEM(U15) CHIP SELECT (LOW
A C T I V E )
- /RAMCS : SRAM (U14) CHIP SELECT (LOW
A C T I V E )
When each CHIP SELECT is low, data can be read or
w r i t t e n .
• D0 - D15
- 16bit data bus
• A0 - A 1 7
- ADDRESS BUS (A18 - A21 are re s e r v e d . )