ACPI Control (ACTL) – Offset 1bd8 - 001 - ID:834576 | Intel® 800 Series Chipset Family Platform Controller Hub (PCH), Volume 2

Intel® 800 Series Chipset Family Platform Controller Hub (PCH), Volume 2

ID	Date	Version	Classification
834576	10/10/2024	001	Public

ACPI Control (ACTL) – Offset 1bd8

Bit Range	Default	Access	Field Name and Description
31:8	0h	RO	Reserved
7	0h	RW	ACPI Enable (EN) When set, decode of the I/O range pointed to by the ACPI base register is enabled and the ACPI power management function is enabled.
6	0h	RO	Reserved
5:3	0h	RW	GPE1 SCI IRQ Select (G1SCIS) Specifies on which IRQ the SCI will internally appear. If not using the APIC, the SCI must be routed to IRQ[9-11], and that interrupt is not sharable with the SERIRQ stream, but is shareable with other PCI interrupts. If using the APIC, the SCI can also be mapped to IRQ20-23, and can be shared with other interrupts. Bits - SCI Map ---- - ------- 000 - IRQ9 001 - IRQ10 010 - IRQ11 011 - Reserved 100 - IRQ20 (only if APIC is enabled) 101 - IRQ21 (only if APIC is enabled) 110 - IRQ22 (only if APIC is enabled) 111 - IRQ23 (only if APIC is enabled) When the interrupt is mapped to APIC interrupts 9, 10 or 11, the APIC should be programmed for active-high reception. When the interrupt is mapped to APIC interrupts 20 through 23, the APIC should be programmed for active-low reception.
2:0	0h	RW	SCI IRQ Select (SCIS) Specifies on which IRQ the SCI will internally appear. If not using the APIC, the SCI must be routed to IRQ[9-11], and that interrupt is not sharable with the SERIRQ stream, but is shareable with other PCI interrupts. If using the APIC, the SCI can also be mapped to IRQ20-23, and can be shared with other interrupts. Bits - SCI Map ---- - ------- 000 - IRQ9 001 - IRQ10 010 - IRQ11 011 - Reserved 100 - IRQ20 (only if APIC is enabled) 101 - IRQ21 (only if APIC is enabled) 110 - IRQ22 (only if APIC is enabled) 111 - IRQ23 (only if APIC is enabled) When the interrupt is mapped to APIC interrupts 9, 10 or 11, the APIC should be programmed for active-high reception. When the interrupt is mapped to APIC interrupts 20 through 23, the APIC should be programmed for active-low reception.