Land Listing and Signal Descriptions
Dual-Core Intel® Xeon® Processor 3000 Series Datasheet 71
IGNNE# Input IGNNE# (Ignore Numeric Error) is asserted to the processor to ignore
a numeric error and continue to execute noncontrol floating-point
instructions. If IGNNE# is de-asserted, the processor generates an
exception on a noncontrol floating-point instruction if a previous
floating-point instruction caused an error. IGNNE# has no effect when
the NE bit in control register 0 (CR0) is set.
IGNNE# is an asynchronous signal. However, to ensure recognition of
this signal following an Input/Output write instruction, it must be valid
along with the TRDY# assertion of the corresponding Input/Output
Write bus transaction.
INIT# Input INIT# (Initialization), when asserted, resets integer registers inside
the processor without affecting its internal caches or floating-point
registers. The processor then begins execution at the power-on Reset
vector configured during power-on configuration. The processor
continues to handle snoop requests during INIT# assertion. INIT# is
an asynchronous signal and must connect the appropriate pins/lands
of all processor FSB agents.
ITP_CLK[1:0] Input ITP_CLK[1:0] are copies of BCLK that are used only in processor
systems where no debug port is implemented on the system board.
ITP_CLK[1:0] are used as BCLK[1:0] references for a debug port
implemented on an interposer. If a debug port is implemented in the
system, ITP_CLK[1:0] are no connects in the system. These are not
processor signals.
LINT[1:0] Input LINT[1:0] (Local APIC Interrupt) must connect the appropriate
pins/lands of all APIC Bus agents. When the APIC is disabled, the
LINT0 signal becomes INTR, a maskable interrupt request signal, and
LINT1 becomes NMI, a nonmaskable interrupt. INTR and NMI are
backward compatible with the signals of those names on the Pentium
processor. Both signals are asynchronous.
Both of these signals must be software configured via BIOS
programming of the APIC register space to be used either as
NMI/INTR or LINT[1:0]. Because the APIC is enabled by default after
Reset, operation of these signals as LINT[1:0] is the default
configuration.
LOCK# Input/Output LOCK# indicates to the system that a transaction must occur
atomically. This signal must connect the appropriate pins/lands of all
processor FSB agents. For a locked sequence of transactions, LOCK#
is asserted from the beginning of the first transaction to the end of the
last transaction.
When the priority agent asserts BPRI# to arbitrate for ownership of
the processor FSB, it will wait until it observes LOCK# de-asserted.
This enables symmetric agents to retain ownership of the processor
FSB throughout the bus locked operation and ensure the atomicity of
lock.
MSID[1:0] Output These signals indicate the Market Segment for the processor. Refer to
Table 2-2 for additional information.
PECI Input/Output PECI is a proprietary one-wire bus interface. See Section 5.4 for
details.
PROCHOT# Input/Output As an output, PROCHOT# (Processor Hot) will go active when the
processor temperature monitoring sensor detects that the processor
has reached its maximum safe operating temperature. This indicates
that the processor Thermal Control Circuit (TCC) has been activated, if
enabled. As an input, assertion of PROCHOT# by the system will
activate the TCC, if enabled. The TCC will remain active until the
system de-asserts PROCHOT#. See Section 5.2.4 for more details.
PWRGOOD Input PWRGOOD (Power Good) is a processor input. The processor requires
this signal to be a clean indication that the clocks and power supplies
are stable and within their specifications. ‘Clean’ implies that the
signal will remain low (capable of sinking leakage current), without
glitches, from the time that the power supplies are turned on until
they come within specification. The signal must then transition
monotonically to a high state. PWRGOOD can be driven inactive at
any time, but clocks and power must again be stable before a
subsequent rising edge of PWRGOOD.
The PWRGOOD signal must be supplied to the processor; it is used to
protect internal circuits against voltage sequencing issues. It should
be driven high throughout boundary scan operation.
Table 4-3. Signal Description (Sheet 4 of 7)
Name Type Description
