FW82371EB Intel, FW82371EB Datasheet - Page 29

• Manufacturer Part Number: FW82371EB
• Manufacturer: Intel

Specifications of FW82371EB

• Lead Free Status / RoHS Status: Not Compliant

3.
Specification Update
R
IRQ8# Routing
The RTC interrupt is connected to ISA IRQ8#, and is internally routed within the PIIX4.
If the internal RTC is enabled (bit 0 of the RTCCFG is set ) , the PIIX4’s IRQ8# pin should be
programmed as a general-purpose input, GPI[6] (by setting bit 14 of the PIIX4’s General Configuration
Register) . However, if an external APIC is used, the PIIX4’s IRQ8# becomes an output and must not be
programmed as a general-purpose input.
The table below summarizes the PIIX4’s IRQ8# pin configuration depending on different usage of the
RTC and APIC.
This clarification applies to all steppings of the PIIX4 and will be incorporated into the next revision of
the PIIX4 datasheet.
IRQ8# configuration with different scenarios
*Bit 14 of the PIIX4’s GENCFG register will determine the configuration of PIIX4’s IRQ8# pin.
Internal RTC
Not used
Not used
Used
Used
External RTS
Not used
Not used
Used
Used
External APIC
Not used
Not used
Used
Used
Intel
PIIX4’s IRQ Should be
®
IRQ8# (output)
82371EB (PIIX4E)
Selected as *
IRQ8# (input)
IRQ8# (input)
GPI[6] (input)
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