RG82845SL5YQ Datasheet, PDF (23/148 Pages) Intel Corporation – Intel® 845 Chipset: 82845 Memory Controller Hub (MCH) for SDR

Signal Description
R
2.2
2.3
SDR SDRAM Interface Signals
Signal Name
Type
Description
SCS[11:0]#
SMA[12:0]
SBS[1:0]
SRAS#
SCAS#
SWE#
SDQ[63:0]
SCB[7:0]
SCKE[5:0]
RDCLKO
RDCLKIN
O
CMOS
O
CMOS
O
CMOS
O
CMOS
O
CMOS
O
CMOS
I/O
CMOS
I/O
CMOS
O
CMOS
O
CMOS
I
CMOS
Chip Select: These signals select the particular SDRAM components
during the active state.
Note: There are two SCS# signals per SDRAM row. These signals can
be toggled on every rising system memory clock edge.
Multiplexed Memory Address: These signals are used to provide the
multiplexed row and column address to SDRAM.
Memory Bank Select: SBS[1:0] define the banks that are selected within
each SDRAM row. The SMA and SBS signals combine to address every
possible location in a SDRAM device.
SDRAM Row Address Strobe: SRAS# is Used with SCAS# and SWE#
(along with SCS#) to define the DRAM commands.
SDRAM Column Address Strobe: SCAS# is used with SRAS# and
SWE# (along with SCS#) to define the SDRAM commands.
Write Enable: SWE# is used with SCAS# and SRAS# (along with SCS#)
to define the SDRAM commands.
Data Lines: These signals are used to interface to the SDRAM data bus.
Check Bit Data Lines: These signals are used to interface to the
SDRAM ECC signals.
Clock Enable: These pins are used to signal a self-refresh or
Powerdown command to a SDRAM array when entering system
suspend. SCKE is also used to dynamically powerdown inactive SDRAM
rows. There is one SCKE per SDRAM row. These signals can be toggled
on every rising SCLK edge.
Clock Output: RDCLKO is used to emulate source-synch clocking for
reads. This signal connects to RDCLKIN.
Clock Input: RDCLKIN is used to emulate source-synch clocking for
reads. This signal connects to RDCLKO.
Hub Interface Signals
Signal Name
Type
Description
HI_[10:0]
HI_STB
HI_STB#
I/O
CMOS
I/O
CMOS
I/O
CMOS
Hub Interface Signals: Signals used for the hub interface.
Hub Interface Strobe: One of two differential strobe signals used to
transmit or receive packet data over the hub interface.
Hub Interface Strobe Compliment: One of two differential strobe
signals used to transmit or receive packet data over the hub interface.
Intel^® 82845 MCH for SDR Datasheet
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