Express-BL
Page 25
3.3.13.
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 3.3VSB
PU 10K
3.3VSB
THRMTRIP#
A35
Active low output indicating that the CPU has entered
thermal shutdown.
O 3.3V
PU 330ohm
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 10k 3.3V
PD only when TPM on
module
3.3.14.
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 8.2K 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 8.2K 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
3.3.15.
I2C Bus
Signal
Pin # Description
I/O
PU/PD
Comment
I2C_CK
B33
General purpose I²C port clock output/input
I/O OD 3.3VSB
PU 2k2 3.3VSB
Source SEMA BMC
I2C_DAT
B34
General purpose I²C port data I/O line
I/O OD 3.3VSB
PU 2k2 3.3VSB
Source SEMA BMC
Содержание COM Express Express-BL
Страница 13: ...Express BL Page 13 2 17 Functional Diagram AB CD FDI DMI...
Страница 14: ...Page 14 2 18 Mechanical Dimensions...