Specification Sheet
Datasheet, Volume 1 of 2 29
Signal Descriptions
4.2 PCI Express* Based Interface Signals
Note: PCI Express* Ports 1, 2 and 3 Signals are receive and transmit differential pairs.
4.3 Direct Media Interface 3 (DMI3) Signals
Table 4-2. Memory Channel Miscellaneous
Signal Name Description
DDR {012,345}_RESET_N
System memory reset: Reset signal from processor to DRAM devices on
the DIMMs. DDR012_RESET_N is used for memory channels 0, 1 and 2
while DDR345_RESET_N is used for memory channels 3, 4 and 5.
DDR{012,345}_SPDSCL
SMBus clock for the dedicated interface to the serial presence detect
(SPD) and thermal sensors (TSoD) on the DIMMs. DDR_SCL_C012 is used
for memory channels 0, 1 and 2 while DDR_SCL_C345 is used for memory
channels 3, 4 and 5.
DDR{012,345}_SPDSDA
SMBus data for the dedicated interface to the serial presence detect (SPD)
and thermal sensors (TSoD) on the DIMMs. DDR_SDA_C012 is used for
memory channels 0, 1 and 2 while DDR_SDA_C345 is used for memory
channels 3, 4 and 5.
DDR{5:0}_CAVREF DIMM Command address VREF signal
DDR{012,345}_DRAM_PWR_OK
Power good for VCCD rail used by the DRAM. This is an input signal used
to indicate the VCCD power supply is stable for memory channels 0, 1, 2
and channels 3, 4, 5.
DDR{012,345}_RCOMP[2:0] DDR Compensation resistance control
Table 4-3. PCI Express Signals
Signal Name Description
PE{3:1}_RX_DN/DP[15:0] PCIe Receive Data Input
PE{3:1}_TX_DN/DP[15:0] PCIe Transmit Data Output
Table 4-4. PCI Express Miscellaneous Signals
Signal Name Description
PE_HP_SCL
PCI Express Hot-Plug SMBus Clock: Provides PCI Express* hot-plug support
via a dedicated SMBus interface. Requires an external general purpose
input/output (GPIO) expansion device on the platform.
PE_HP_SDA
PCI Express Hot-Plug SMBus Data: Provides PCI Express* hot-plug support
via a dedicated SMBus interface. Requires an external general purpose
input/output (GPIO) expansion device on the platform.
Table 4-5. DMI3 Signals
Signal Name Description
DMI_RX_DN/DP[3:0]
DMI3 Receive Data Input
DMI_TX_DN/DP[3:0]
DMI3 Transmit Data Output