11 spi (bios only), 12 miscellaneous, 13 smbus – ADLINK Express-HLE User Manual
Page 22

Page 22
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
