BX80547PG3200FSL8Q6 Datasheet, PDF (86/105 Pages) Intel Corporation – Intel® Pentium® 4 Processor 6xxΔ Sequence and Intel® Pentium® 4 Processor Extreme Edition

Features
6.2
Clock Control and Low Power States
The processor allows the use of AutoHALT and Stop-Grant states to reduce power consumption by
stopping the clock to internal sections of the processor, depending on each particular state. See
Figure 6-1 for a visual representation of the processor low power states.
Figure 6-1. Processor Low Power State Machine
Norm al State
Normal execution
HALT or MWAIT Instruction and
HALT Bus Cycle Generated
INIT#, BINIT#, INTR, NMI, SMI#,
RESET#, FSB interrupts
Enhanced HALT or HALT State
BCLK running
Snoops and interrupts allow ed
STPCLK#
Asserted
STPCLK# De-
asserted
STAPsCsLeKrt#edSTDPeC-LaKss#erted
Stop-Grant State
BCLK running
Snoops and interrupts allow ed
Snoop Event Occurs
Snoop Event Serviced
Snoop
Event
Occurs
Snoop
Event
Serviced
Enhanced HALT Snoop or HALT
Snoop State
BCLK running
Service snoops to caches
Grant Snoop State
BCLK running
Service snoops to caches
6.2.1
Normal State
This is the normal operating state for the processor.
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Datasheet