Intel III M 866 MHz BXM80530B866512 数据表
产品代码
BXM80530B866512
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
Low-voltage 600 MHz, Ultra Low-voltage 600 MHz and Ultra Low-voltage 500 MHz
66 Datasheet
283653-002
7.
Processor Initialization and
Configuration
Configuration
7.1 Description
The mobile Pentium III processor has some configuration options that are determined by hardware
and some that are determined by software. The processor samples its hardware configuration at
reset on the active-to-inactive transition of RESET#. Most of the configuration options for the
mobile Pentium III processor are identical to those of the Pentium II processor. The Pentium
and some that are determined by software. The processor samples its hardware configuration at
reset on the active-to-inactive transition of RESET#. Most of the configuration options for the
mobile Pentium III processor are identical to those of the Pentium II processor. The Pentium
®
II
Processor Developer’s Manual describes these configuration options. New configuration options
for the mobile Pentium III processor are described in the remainder of this section.
for the mobile Pentium III processor are described in the remainder of this section.
7.1.1 Quick
Start
Enable
The processor normally enters the Stop Grant state when the STPCLK# signal is asserted but it
will enter the Quick Start state instead if A15# is sampled active on the RESET# signal’s active-
to-inactive transition. The Quick Start state supports snoops from the bus priority device like the
Stop Grant state but it does not support symmetric master snoops nor is the latching of interrupts
supported. A “1” in bit position 5 of the Power-on Configuration register indicates that the Quick
Start state has been enabled.
will enter the Quick Start state instead if A15# is sampled active on the RESET# signal’s active-
to-inactive transition. The Quick Start state supports snoops from the bus priority device like the
Stop Grant state but it does not support symmetric master snoops nor is the latching of interrupts
supported. A “1” in bit position 5 of the Power-on Configuration register indicates that the Quick
Start state has been enabled.
7.1.2
System Bus Frequency
The current generation mobile Pentium III processor will only function with a system bus
frequency of 100 MHz. Bit positions 18 to 19 of the Power-on Configuration register indicates at
which speed a processor will run. A “00” in bits [19:18] indicates a 66-MHz bus frequency, a “10”
indicates a 100-MHz bus frequency, and a “01” indicates a 133-MHz bus frequency.
frequency of 100 MHz. Bit positions 18 to 19 of the Power-on Configuration register indicates at
which speed a processor will run. A “00” in bits [19:18] indicates a 66-MHz bus frequency, a “10”
indicates a 100-MHz bus frequency, and a “01” indicates a 133-MHz bus frequency.
7.1.3 APIC
Enable
If the PICD0 signal is sampled low on the active-to-inactive transition of the RESET# signal then
the PICCLK signal can be tied to V
the PICCLK signal can be tied to V
SS
. Otherwise the PICD[1:0] signals must be pulled up to V
CCT
and PICCLK must be supplied. Driving PICD0 low at reset also has the effect of clearing the
APIC Global Enable bit in the APIC Base MSR. This bit is normally set when the processor is
reset, but when it is cleared the APIC is completely disabled until the next reset.
APIC Global Enable bit in the APIC Base MSR. This bit is normally set when the processor is
reset, but when it is cleared the APIC is completely disabled until the next reset.
7.2
Clock Frequencies and Ratios
The mobile Pentium III processor uses a clock design in which the bus clock is multiplied by a
ratio to produce the processor’s internal (or “core”) clock. Unlike some of the mobile Pentium II
processors, the ratio used is programmed into the processor during manufacturing. The bus ratio
programmed into the processor is visible in bit positions 22 to 25 and bit 27 of the Power-on
Configuration register. Table 14 shows the 5-bit codes in the Power-on Configuration register and
their corresponding bus ratios.
ratio to produce the processor’s internal (or “core”) clock. Unlike some of the mobile Pentium II
processors, the ratio used is programmed into the processor during manufacturing. The bus ratio
programmed into the processor is visible in bit positions 22 to 25 and bit 27 of the Power-on
Configuration register. Table 14 shows the 5-bit codes in the Power-on Configuration register and
their corresponding bus ratios.