Features
6
Features
6.1
Power-On Configuration Options
Several configuration options can be configured by hardware. The Pentium 4 processor
samples the hardware configuration at reset, on the active-to-inactive transition of
RESET#. For specifications on these options, refer to Table 34.
The sampled information configures the processor for subsequent operation. These
configuration options cannot be changed except by another reset. All resets reconfigure
the processor; for reset purposes, the processor does not distinguish between a
"warm" reset and a "power-on" reset.
Table 34.
Power-On Configuration Option Signals
Configuration Option
Output tristate
Signal1,2
SMI#
INIT#
Execute BIST
In Order Queue pipelining (set IOQ depth
to 1)
A7#
Disable MCERR# observation
Disable BINIT# observation
APIC Cluster ID (0-3)
A9#
A10#
A[12:11]#
A15#
Disable bus parking
Disable Hyper-Threading Technology
Symmetric agent arbitration ID
A31#
BR0#
A[6:3]#, A8#, A[14:13]#,
A[16:35]#
RESERVED
NOTES:
1. Asserting this signal during RESET# will select the corresponding option.
2. Address signals not identified in this table as configuration options should not be asserted
during RESET#.
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 16 for a visual representation of the processor low
power states.
Datasheet
85
INTEL [ INTEL ]
