Pin Listing and Signal Descriptions
Table 4-3. Signal Description (Sheet 7 of 8)
Name
Type
Description
SLP# (Sleep), when asserted in Stop-Grant state, causes the processor to enter
the Sleep state. During Sleep state, the processor stops providing internal clock
signals to all units, leaving only the Phase-Locked Loop (PLL) still operating.
Processors in this state will not recognize snoops or interrupts. The processor
will recognize only assertion of the RESET# signal, and de-assertion of SLP#. If
SLP# is de-asserted, the processor exits Sleep state and returns to Stop-Grant
state, restarting its internal clock signals to the bus and processor core units.
SLP#
SMI#
Input
SMI# (System Management Interrupt) is asserted asynchronously by system
logic. On accepting a System Management Interrupt, the processor saves the
current state and enter System Management Mode (SMM). An SMI
Acknowledge transaction is issued, and the processor begins program execution
from the SMM handler.
Input
Input
If SMI# is asserted during the de-assertion of RESET#, the processor will tristate
its outputs.
STPCLK# (Stop Clock), when asserted, causes the processor to enter a low
power Stop-Grant state. The processor issues a Stop-Grant Acknowledge
transaction, and stops providing internal clock signals to all processor core units
except the FSB and APIC units. The processor continues to snoop bus
transactions and service interrupts while in Stop-Grant state. When STPCLK# is
de-asserted, the processor restarts its internal clock to all units and resumes
execution. The assertion of STPCLK# has no effect on the bus clock; STPCLK#
is an asynchronous input.
STPCLK#
TCK (Test Clock) provides the clock input for the processor Test Bus (also known
as the Test Access Port).
TCK
Input
Input
TDI (Test Data In) transfers serial test data into the processor. TDI provides the
serial input needed for JTAG specification support.
TDI
TDO (Test Data Out) transfers serial test data out of the processor. TDO
provides the serial output needed for JTAG specification support.
TDO
Output
Input
TESTHI[12:0] must be connected to a V power source through a resistor for
CC
TESTHI[12:0]
proper processor operation. See Section 2.5 for more details.
THERMDA
THERMDC
Other Thermal Diode Anode. See Section 5.2.6.
Other Thermal Diode Cathode. See Section 5.2.6.
In the event of a catastrophic cooling failure, the processor will automatically
shut down when the silicon has reached a temperature approximately 20 °C
above the maximum T . Assertion of THERMTRIP# (Thermal Trip) indicates the
C
processor junction temperature has reached a level beyond which permanent
silicon damage may occur. Upon assertion of THERMTRIP#, the processor will
shut off its internal clocks (thus halting program execution) in an attempt to
reduce the processor junction temperature. To protect the processor, its core
THERMTRIP#
Output voltage (V ) must be removed following the assertion of THERMTRIP#. Driving
CC
of the THERMTRIP# signal is enabled within 10 µs of the assertion of
PWRGOOD and is disabled on de-assertion of PWRGOOD. Once activated,
THERMTRIP# remains latched until PWRGOOD is de-asserted. While the de-
assertion of the PWRGOOD signal will de-assert THERMTRIP#, if the
processor’s junction temperature remains at or above the trip level,
THERMTRIP# will again be asserted within 10 µs of the assertion of
PWRGOOD.
TMS (Test Mode Select) is a JTAG specification support signal used by debug
TMS
Input
tools.
TRDY# (Target Ready) is asserted by the target to indicate that it is ready to
TRDY#
TRST#
Input
Input
receive a write or implicit writeback data transfer. TRDY# must connect the
appropriate pins of all FSB agents.
TRST# (Test Reset) resets the Test Access Port (TAP) logic. TRST# must be
driven low during power on Reset.
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Datasheet