ADLINK Technology cExpress-AL, User Manual

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cExpress-AL
Pinouts and Signal Descriptions
19
3.3.10. 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
PU 10k
3.3VSB
Only supports CS0
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
3.3VSB
Carrier shall pull to
GND or leave not-
connected.
BIOS_DIS1# B88 Selection strap to determine the BIOS boot
device.
I PU 10k
3.3VSB Carrier shall pull to
GND or leave not-
connected
3.3.11. Miscellaneous
Signal Pin Description I/O PU/PD Comment
SPKR B32 Output for audio enunciator, the “speaker”
in PC-AT systems O 3.3V PU 10k
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 Recommend to
add PU on carrier
board
THRMTRIP# A35 Active low output indicating that the CPU
has entered thermal shutdown. O 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 PU 2.2k
3.3V There shall be PD
on carrier board
FAN_TACHIN B102 Fan tachometer input for a fan with a two
pulse output. I OD 3.3V PU 10k
3.3V
TPM_PP A96 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 only when TPM
on module
RAPID_SHUTDOWN C67 Trigger for Rapid Shutdown. Must be driven
to 5V though a <=50 ohm source
impedance for
≥ 20 μ s.
I 5.0VSB Not supported