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cExpress-HL
Signal
Pin # Description
I/O
PU/PD
Comment
GPO[3]
B63
General purpose output pins.
O 3.3V
After hardware
RESET output low
GPI[0]
A54
General purpose input pins.
Pulled high internally on the module.
I 3.3V
PU 10K 3.3V
GPI[1]
A63
General purpose input pins.
Pulled high internally on the module.
I 3.3V
PU 10K 3.3V
GPI[2]
A67
General purpose input pins.
Pulled high internally on the module.
I 3.3V
PU 10K 3.3V
GPI[3]
A85
General purpose input pins.
Pulled high internally on the module.
I 3.3V
PU 10K 3.3V
3.3.16
Serial Interface Signals
Signal
Pin # Description
I/O
PU/PD
Comment
SER0_TX A98
General purpose serial port transmitter (TTL level output)
O CMOS
Power rail tolerance 5V / 12V
SER0_RX A99
General purpose serial port receiver (TTL level input)
I CMOS
Power rail tolerance 5V / 12V
SER1_TX A101 General purpose serial port transmitter (TTL level output)
O CMOS
Power rail tolerance 5V / 12V
SER1_RX A102 General purpose serial port receiver (TTL level input)
I CMOS
Power rail tolerance 5V / 12V
3.3.17
Power and System Management
Signal
Pin # Description
I/O
PU/PD
Comment
PWRBTN#
B12
Power button to bring system out of S5 (soft off), active on falling edge.
I 3.3VSB
PU 10k
3.3VSB
SYS_RESET#
B49
Reset button input. Active low request for module to reset and reboot. May
be falling edge sensitive. For situations when SYS_RESET# is not able to
reestablish control of the system, PWR_OK or a power cycle may be used.
I 3.3VSB
PU 10k
3.3VSB
CB_RESET#
B50
Reset output from module to Carrier Board. Active low. Issued by module
chipset and may result from a low SYS_RESET# input, a low PWR_OK
input, a VCC_12V power input that falls below the minimum specification, a
watchdog timeout, or may be initiated by the module software.
O 3.3VSB
PWR_OK
B24
Power OK from main power supply. A high value indicates that the power is
good. This signal can be used to hold off Module startup to allow carrier
based FPGAs or other configurable devices time to be programmed.
I 3.3V
PU 100k
3.3VSB
SUS_STAT#
B18
Indicates imminent suspend operation; used to notify LPC devices.
O 3.3VSB
SUS_S3#
A15
Indicates system is in Suspend to RAM state. Active-low output. An inverted
copy of SUS_S3# on the carrier board (also known as “PS_ON”) may be
used to enable the non-standby power on a typical ATX power supply.
O 3.3VSB
SUS_S4# A18
Indicates
system is in Suspend to Disk state. Active low output.
O 3.3VSB
SUS_S5#
A24
Indicates system is in Soft Off state.
O 3.3VSB
WAKE0#
B66
PCI Express wake up signal.
I 3.3VSB
PU 10k
3.3VSB
WAKE1#
B67
General purpose wake up signal. May be used to implement wake-up on
PS/2 keyboard or mouse activity.
I 3.3VSB
PU 10k
3.3VSB
BATLOW#
A27
Battery low input. This signal may be driven low by external circuitry to
signal that the system battery is low, or may be used to signal some other
external power-management event.
I 3.3VSB
PU 10k
3.3VSB
