Datasheet

Mobile Intel
®
Pentium
®
III Processor in BGA2 and Micro-PGA2 Packages at 1 GHz,
900 MHz, 850 MHz, 800 MHz, 750 MHz, 700 MHz, Low-voltage 750 MHz, Low-voltage
700 MHz, Low-voltage 600 MHz, Ultra Low-voltage 600 MHz and Ultra Low-voltage 500 MHz
283653-002 Datasheet 73
LOCK# (I/O - GTL+)
The LOCK# (Lock) signal indicates to the system that a sequence of transactions must occur
atomically. This signal must be connected to the appropriate pins/balls on both agents on the
system bus. For a locked sequence of transactions, LOCK# is asserted from the beginning of the
first transaction through the end of the last transaction.
When the priority agent asserts BPRI# to arbitrate for bus ownership, it waits until it observes
LOCK# deasserted. This enables the processor to retain bus ownership throughout the bus locked
operation and guarantee the atomicity of lock.
NC (No Connect)
All signals named NC (No Connect) must be unconnected.
NMI (I - 1.5V Tolerant)
The NMI (Non-Maskable Interrupt) indicates that an external interrupt has been generated. NMI
becomes the LINT1 signal when the APIC is disabled. Asserting NMI causes an interrupt with an
internally supplied vector value of 2. An external interrupt-acknowledge transaction is not
generated. If NMI is asserted during the execution of an NMI service routine, it remains pending
and is recognized after the IRET is executed by the NMI service routine. At most, one assertion of
NMI is held pending. NMI is rising edge sensitive.
PICCLK (I - 2.5V Tolerant)
The PICCLK (APIC Clock) signal is an input clock to the processor and system logic or I/O APIC
that is required for operation of the processor, system logic, and I/O APIC components on the
APIC bus.
PICD[1:0] (I/O - 1.5V Tolerant Open-drain)
The PICD[1:0] (APIC Data) signals are used for bi-directional serial message passing on the APIC
bus. They must be connected to the appropriate pins/balls of all APIC bus agents, including the
processor and the system logic or I/O APIC components. If the PICD0 signal is sampled low on
the active-to-inactive transition of the RESET# signal, then the APIC is hardware disabled.
PLL1, PLL2 (Analog)
The PLL1 and PLL2 signals provide isolated analog decoupling is required for the internal PLL.
See Section 3.2.2 for a description of the analog decoupling circuit.
PRDY# (O - GTL+)
The PRDY# (Probe Ready) signal is a processor output used by debug tools to determine
processor debug readiness.