I82371MX Datasheet, PDF (19/133 Pages) Intel Corporation – INTEL 430MX PCISET 82371MX MOBILE PCI I/O IDE XCELERATOR (MPIIX)

E
82371MX (MPIIX)
2.7. System Power Management (SMM) Signals
Signal Name
Type
PCIRST#
Description
SMI#
O
3.3V
TTL
4mA
High
SYSTEM MANAGEMENT INTERRUPT: SMI# is an
active low synchronous output that is asserted by the
MPIIX in response to one of many enabled hardware or
software events. During CPU Reset (INIT and
CPURST), this signal is negated.
STPCLK#
O
3.3V
TTL
4mA
High
STOP CLOCK: STPCLK# is an active low synchronous
output that is asserted by the MPIIX in response to one
of many hardware or software events. STPCLK#
connects directly to the CPU and is synchronous to
PCICLK.
SUSTAT#
O
5/3V
CMOS
4mA
High
SUSPEND STATUS: This output signal is used to
switch off power to all non-critical devices during
suspend. Activation of this signal is typically the last
step in the SMM code.
SYSACT#
I
5V
pu50KΩ
TTL
SYSTEM ACTIVITY: This input signal can be used by
system devices such as bridge chips to indicate system
activity that is not visible to the MPIIX power
management logic. This signal, if enabled through setup
software, can be used by MPIIX to prevent the system
from entering an idle state.
SRBTN#
I
5/3V
CMOS
SUSPEND RESUME BUTTON: This signal can be
enabled to generates an SMI# request. SRBTN# is
monitored by the low power “Resume Well” circuitry
during suspend. This signal must always be driven to a
valid logic level.
BATLOW#
I
5/3V
CMOS
BATTERY LOW: BATLOW# Indicates that battery
power is low. Assertion of this signal triggers an SMI, if
enabled. This signal is monitored by the low power
“Resume Well” circuitry during suspend. MPIIX can be
programmed to prevent a resume operation when the
BATLOW# signal is active. This signal must always be
driven to a valid logic level. Once asserted, this signal
must remain asserted until SMI# is generated.
RSMRST#
I
5/3V
CMOS
RESUME RESET: This signal acts as a reset to the low
power “Resume Well” circuitry. This signal must always
be driven to a valid logic level.
SMOUT[5:0]/
DOE#,
RTCALE
O
5V
TTL
4mA
High
SYSTEM MANAGEMENT OUTPUT ENABLES: These
six programmable outputs can be connected to control
the power circuits for various devices in the system.
SMOUT5 can be configured to generate a DISK Output
Enable. SMOUT4 can be configured to generate
RTCALE.
COMRI#
I
5/3V
pu50KΩ
CMOS
COM RING INDICATE: A modem connected to the
COM port will asserts this signal to wake up a
suspended system. This signal is monitored by the low
power “Resume Well” circuitry during suspend.
PRELIMINARY
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