IBASE Technology ET976, Design Manual

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COM Express® Carrier Board Design Guide 59
2.18 Miscellaneous Signals
Table 18: Miscellaneous Signals
Signal Pin Description I/O Remarks
TYPE0#
TYPE1#
TYPE2#
C54
C57
D57
The Type pins indicate the COM Express pin-out type of the
Module. To indicate the Module's pin-out type, the pins are
either not connected or strapped to ground on the Module. The
Carrier Board has to implement additional logic, which prevents
the system to switch power on, if a Module with an incompatible
pin-out type is detected.
O 5V
PDS
Only Available on
T2-T6
TYPE10# A97
Indicates to the Carrier Board that a Type 10 Module is
installed. Indicates to the Carrier Board, that a Rev 1.0/2.0
Module is installed.
TYPE10#
NC Pin-out R2.0
PD Pin-out Type 10 pull down to ground with 47k
12V Pin-out R1.0
SPKR B32
Output used to control an external FET or a logic gate to
drive an external PC speaker.
O 3.3V
CMOS
BIOS_DISABLE0# A34
Selection straps to determine the BIOS boot device. The
Carrier should only float these or pull them low,
I 3.3V
CMOS
Refer to SPI –
Serial
Peripheral
Interface B s
BIOS_DISABLE1# B88
Selection straps to determine the BIOS boot device. The
Carrier should only float these or pull them low,
I 3.3V
CMOS
Refer to SPI –
Serial
Peripheral
Interface Bus
WDT B27
Output indicating that a watchdog time-out event has
occurred.
O 3.3V
CMOS
KBD_RST# A86
Input signal of the Module used by an external keyboard
controller to force a system reset.
I 3.3V
CMOS
Only Available on
T1-T5
KBD_A20GATE A87
Input signal of the Module used by an external keyboard
controller to control the CPU A20 gate line. The A20 gate
restricts the memory access to the bottom megabyte of the
system. Pulled high on the Module.
I 3.3V
CMOS
Only Available on
T1-T5
LID# A103 LID switch.
Low active signal used by the ACPI operating system for a
LID switch.
I 3.3V
CMOS OD
Only Available on
T6 and T10
SLEEP# B103 Sleep button.
Low active signal used by the ACPI operating system to
bring the system to sleep state or to wake it up again.
I 3.3V
CMOS OD
Only Available on
T6 and T10
FAN_PWMOUT1
B101 Fan speed control. Uses the Pulse Width Modulation
(PWM) technique to control the fan’s RPM.
O 3.3V
CMOS OD
Only Available on
T6 and T10
FAN_TACHIN1
B102 Fan tachometer input for a fan with a two pulse output.
I 3.3V
CMOS OD
Only Available on
T6 and T10
TPM_PP1
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
CMOS
Only Available on
T6 and T10
GPO0
GPO1
GPO2
GPO3
A93
B54
B57
B63
General Purpose Outputs for system specific usage.
O 3.3V
CMOS
Refer to the
Module's users
guide for
information of the
signals
GPI0
GPI1
GPI2
GPI3
A54
A63
A67
A85
General Purpose Input for system specific usage. The
signals are pulled up by the Module.
I 3.3V
CMOS
Refer to the
Module's users
guide for
information of the
signals