User’s Manual
ESM-2850 User’s Manual
31
2.4.2.1.9 Power & System Management Signals
Signal Signal Description
SUS_S3# Indicates system is in Suspend to RAM state. Active low output.
SUS_S4# Indicates system is in Suspend to Disk state. Active low output.
SUS_S5#
Indicates system is in Soft Off state. Also known as "PS_ON" and can be used to
control an ATX power supply.
BATLOW# Indicates that external battery is low
PWRBTN# Power button to bring system out of S5 (soft off), active on rising edge.
SMB_CK
System Management Bus bidirectional clock line. Power sourced through 5V
standby rail and main power rails.
SMB_DTA
System Management Bus bidirectional data line. Power sourced through 5V
standby rail and main power rails.
SMB_ALERT#
System Management Bus Alert - 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.
SUS_STAT# Indicates imminent suspend operation; used to notify LPC devices
PWR_OK Power OK from main power supply
THRMTRIP# Active low output indicating that the CPU has entered thermal shutdown.
THRM# Input from off-module temp sensor indicating and over-temp situation.
SYS_RESET#
Reset button input. Active low input. System is held in hardware reset while this
input is low, and comes out of reset upon release.
RSMRST#
Resume reset input, active low. Resets power plane logic. May be left open on
carrier board if not used.
WAKE0# PCI Express wake up signal
WAKE1# General purpose wake up signal
2.4.2.1.10 SATA Signals
Signal Signal Description
SATA[0:3]_TX +/- Serial ATA Channel 0-3 transmit differential pair.
SATA[0:3]_RX +/- Serial ATA Channel 0-3receive differential pair.
ATA_ACT# ATA (parallel and serial) activity indicator, active low.
