Intel Pentium Dual Core E2220 187637 データシート
製品コード
187637
Features
88
Datasheet
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
for a visual representation of the processor low
power states.
6.2.1
Normal State
This is the normal operating state for the processor.
6.2.2
HALT and Extended HALT Powerdown States
The processor supports the HALT or Extended HALT powerdown state. The Extended
HALT powerdown must be enabled via the BIOS for the processor to remain within its
specification.
The Extended HALT state is a lower power state as compared to the Stop Grant State.
If Extended HALT is not enabled, the default powerdown state entered will be HALT.
Refer to the sections below for details about the HALT and Extended HALT states.
Figure 22.
Processor Low Power State Machine
Normal State
- Normal Execution
Stop Grant State
- BCLK running
- Snoops and interrupts
allowed
Stop Grant Snoop State
- BCLK running
- Service Snoops to cahces
Extended HALT Snoop or
HALT Snoop State
- BCLK running
- Service Snoops to cahces
Extended HALT or HALT
State
- BCLK running
- Snoops and interrupts
allowed
HALT or MWAIT Instruction and
HALT Bus Cycle Generated
INIT#, BINIT#, INTR, NMI, SMI#,
INIT#, BINIT#, INTR, NMI, SMI#,
RESET#, FSB interrupts
STPCLK#
Asserted
STPCLK#
De-asserted
STPCLK#
Asserted
STPCLK#
De-asserted
Snoop
Event
Occurs
Snoop
Event
Serviced
Snoop Event Occurs
Snoop Event Serviced