Filter
Top Products
2-24 Service Guide
Table 2-2 82371AB Pin Descriptions
Name Type Description
SMBALERT#/
GPI11
I
SM BUS ALERT. Input used by System Management Bus logic to generate an
interrupt (IRQ or SMI) or power management resume event when enabled. If this
function is not needed, this pin can be used as a general-purpose input.
SMBCLK I/O
SM BUS CLOCK. System Management Bus Clock used to synchronize transfer
of data on SMBus.
During Reset: High-Z After Reset: High-Z During POS: High-Z
SMBDATA I/O
SM BUS DATA. Serial data line used to transfer data on SMBus.
During Reset: High-Z After Reset: High-Z During POS: High-Z
SUSA# O
SUSPEND PLANE A CONTROL. Control signal asserted during power
management suspend states. SUSA# is primarily used to control the primary
power plane. This signal is asserted during POS, STR, and STD suspend states.
During Reset: Low After Reset: High During POS: Low
SUSB#/
GPO15
O
SUSPEND PLANE B CONTROL. Control signal asserted during power
management suspend states. SUSB# is primarily used to control the secondary
power plane. This signal is asserted during STR and STD suspend states. If the
power plane control is not needed, this pin can be used as a general-purpose
output.
During Reset: Low After Reset: High During POS: High/GPO
SUSC#/
GPO16
O
SUSPEND PLANE C CONTROL. Control signal asserted during power
management suspend states, primarily used to control the tertiary power plane.
It is asserted only during STD suspend state. If the power plane control is not
needed, this pin can be used as a general-purpose output.
During Reset: Low After Reset: High During POS: High/GPO
SUS_STAT1#/
GPO20
O
SUSPEND STATUS 1. This signal is typically connected to the Host-to-PCI
bridge and is used to provide information on host clock status. SUS_STAST1# is
asserted when the system may stop the host clock, such as Stop Clock or during
POS, STR, and STD suspend states. If this function is not needed, this pin can
be used as a general-purpose output.
During Reset: Low After Reset: High During POS: Low/GPO
SUS_STAT2#/
GPO21
O
SUSPEND STATUS 2. This signal will typically connect to other system
peripherals and is used to provide information on system suspend state. It is
asserted during POS, STR, and STD suspend states. If this function is not
needed, this pin can be used as a general-purpose output.
During Reset: Low After Reset: High During POS: Low/GPO
THRM#/
GPI8
I
THERMAL DETECT. Active low signal generated by external hardware to start
the Hardware Clock Throttling mode. If enabled, the external hardware can force
the system to enter into Hardware Clock Throttle mode by asserting THRM#.
This causes PIIX4 to cycle STPCLK# at a preset programmable rate. If this
function is not needed, this pin can be used as a general-purpose input.
ZZ/
GPO19
O
LOW-POWER MODE FOR L2 CACHE SRAM. This signal is used to power
down a cache’s data SRAMs when the clock logic places the CPU into the Stop
Clock. If this function is not needed, this pin can be used as a general-purpose
output.
During Reset: Low After Reset: Low During POS: Low