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Express-HLE
3.3.11
SPI (BIOS only)
Signal
Pin # Description
I/O
PU/PD
Comment
SPI_CS#
B97
Chip select for Carrier Board SPI BIOS Flash.
O 3.3VSB
SPI_MISO
A92
Data in to module from carrier board SPI BIOS flash.
I 3.3VSB
SPI_MOSI
A95
Data out from module to carrier board SPI BIOS flash.
O 3.3VSB
SPI_CLK
A94
Clock from module to carrier board SPI BIOS flash.
O 3.3VSB
SPI_POWER
A91
Power supply for Carrier Board SPI – sourced from Module
– nominally 3.3V.
The Module shall provide a minimum of 100mA on
SPI_POWER.
Carriers shall use less than 100mA of SPI_POWER.
SPI_POWER shall only be used to power SPI devices on
the Carrier
O P 3.3VSB
BIOS_DIS0#
A34
Selection strap to determine the BIOS boot device.
I
PU 10K 3.3V
Carrier shall pull to GND
or leave no- connect.
BIOS_DIS1#
B88
Selection strap to determine the BIOS boot device.
I
PU 10K 3.3V
Carrier shall pull to GND
or leave no- connect
3.3.12
Miscellaneous
Signal
Pin #
Description
I/O
PU/PD
Comment
SPKR
B32
Output for audio enunciator, the “speaker” in PC-AT
systems
O 3.3V
WDT
B27
Output indicating that a watchdog time-out event has
occurred.
O 3.3V
THRM#
B35
Input from off-module temp sensor indicating an over-temp
situation.
I 3.3V
THERMTRIP#
A35
Active low output indicating that the CPU has entered
thermal shutdown.
O 3.3V
PU 330 3.3V
FAN_PWMOUT
B101
Fan speed control. Uses the Pulse Width Modulation
(PWM) technique to control the fan’s RPM.
O OD 3.3V
FAN_TACHIN11
B102
Fan tachometer input for a fan with a two pulse output.
I OD 3.3V
PU 10k 3.3V
TPM_PP11
C83
Trusted Platform Module (TPM) Physical Presence pin.
Active high. TPM chip has an internal pull down. This
signal is used to indicate Physical Presence to the TPM.
I 3.3V
PD 10k 3.3V
PD is only placed
when TPM is
installed on module
3.3.13
SMBus
Signal
Pin # Description
I/O
PU/PD
Comment
SMB_CK
B13
System Management Bus bidirectional clock line. Power
sourced through 5V standby rail and main power rails.
I/O OD 3.3VSB
PU 2k2 3.3VSB
SMB_DAT#
B14
System Management Bus bidirectional data line. Power
sourced through 5V standby rail and main power rails.
I/O OD 3.3VSB
PU 2k2 3.3VSB
SMB_ALERT#
B15
System Management Bus Alert – active low input can
be used to generate an SMI# (System Management
Interrupt) or to wake the system. Power sourced
through 5V standby rail and main power rails.
I 3.3VSB
PU 10k 3.3VSB