88
Signal
Pin# Description
I/O
Note
ESPI_RESET#
/SUS_STAT#
B18
ESPI Mode: eSPI Reset Reset the eSPI interface
for both master and slaves.
eSPI Reset# is typically driven from eSPI master
to eSPI slaves.
Carrier Board:
Connect to
eSPI Device – eSPI_RESET#
N/C if not used
O 1.8V
Suspend
/ 1.8V
2
ESPI_EN#
B47
This signal is used by the Carrier to indicate the
operating mode of the LPC/eSPI bus. If left
unconnected on the carrier, LPC mode (default)
is selected. If pulled to GND on the carrier, eSPI
mode is selected.
This signal is pulled to a logic
high on the module
through a resistor.
The
Carrier
should only float this line or pull it low.
Carrier Board:
Connect to
N/C : LPC mode
GND: eSPI mode
I NA
CMOS
2
LPC_CLK
B10
LPC clock output 24MHz.
Carrier Board:
Connect to
LPC - LCLK
N/C if not used
O 3.3V
CMOS
ESPI_CK
ESPI Mode: eSPI Master Clock Output This pin
provides the reference timing for all the serial
input and output operations.
Carrier Board:
Connect to
eSPI Device – eSPI_CLK,
the Carrier
shall
have
a 33 Ohm series termination.
N/C if not used
O 1.8V
Suspend
/ 1.8V
2
Note:
1. Implementing external LPC devices on the COM Express Carrier Board always requires
customization of the COM Express Module's BIOS in order to support basic initialization for those LPC
devices. Otherwise the functionality of the LPC devices will not be supported by a Plug&Play or ACPI
capable system.
2. SOM-5992 is not support eSPI.