82801BA Datasheet, PDF (111/498 Pages) Intel Corporation – Intel 82801BA I/O Controller Hub 2 (ICH2) and Intel 82801BAM I/O Controller Hub 2 Mobile

Functional Description
5.8.2 Interrupt Mapping
The I/O APIC within the ICH2 supports 24 APIC interrupts. Each interrupt has its own unique
vector assigned by software. The interrupt vectors are mapped as follows and match “configuration
6” of the Multi-processor specification.
Table 5-18. APIC Interrupt Mapping
IRQ #
Via
Direct from Via PCI
SERIRQ
pin
message
Internal Modules
0
No
No
1
Yes
No
2
No
No
3
Yes
No
4
Yes
No
5
Yes
No
6
Yes
No
7
Yes
No
8
No
No
9
Yes
No
10
Yes
No
11
Yes
No
12
Yes
No
13
No
No
14
Yes
Yes
15
Yes
Yes
16
PIRQA
PIRQA
17
PIRQB
PIRQB
18
PIRQC
PIRQC
19
PIRQD
PIRQD
20
N/A
PIRQE
21
N/A
PIRQF
22
N/A
PIRQG
23
N/A
PIRQH
No
Cascade from 8259 #1
Yes
No
8254 Counter 0
Yes
Yes
Yes
Yes
Yes
No
RTC
Yes
Option for SCI, TCO
Yes
Option for SCI, TCO
Yes
Option for SCI, TCO
Yes
No
FERR# logic
Yes
Yes
No
No
AC’97 Audio, Modem, option for SMbus
No
No
USB #1
Yes
LAN, option for SCI, TCO
Yes
Option for SCI, TCO
Yes
Option for SCI, TCO
Yes
USB #2, option for SCI, TCO
82801BA ICH2 and 82801BAM ICH2-M Datasheet
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