8.2.1 LPC Bus
On the conga-X945/XA945 the PCI Bus acts as the subtractive decoding agent. All I/O
cycles that are not positively decoded are forwarded to the PCI Bus not the LPC Bus.
Only specified I/O ranges are forwarded to the LPC Bus. In the congatec Embedded
BIOS the following I/O address ranges are sent to the LPC Bus:
280 – 2FF
3F8 – 3FF
3E8 – 3EF
A00 – A0F
Parts of these ranges are not available if the devices of the onboard Super I/O are
activated or if an additional Super I/O is used on the carrier board. If you require
additional LPC Bus resources other than those mentioned above, or more information
about this subject, contact congatec technical support for assistance.
8.3 Interrupt Request (IRQ) Lines
Table 38
IRQ Lines in PIC mode
IRQ#
Available
Typical Interrupt Source
Connected to Pin
0
No
Counter 0
Not applicable
1
No
Keyboard
Not applicable
2
No
Cascade Interrupt from Slave PIC
Not applicable
3
Note 1
Serial Port 2 (COM2) / Generic
IRQ3 via SERIRQ
4
Note 1
Serial Port 1 (COM1) / Generic
IRQ4 via SERIRQ
5
Yes
Not applicable
IRQ5 via SERIRQ
6
Note 1
Floppy Drive Controller / Generic
IRQ6 via SERIRQ
7
Note 1
Parallel Port 1 (LPT1) / Generic
IRQ7 via SERIRQ
8
No
Real-time Clock
Not applicable
9
Note 3
SCI / Generic
IRQ9 via SERIRQ
10
Yes
Not applicable
IRQ10 via SERIRQ
11
Yes
Not applicable
IRQ11 via SERIRQ
12
Note 1
PS/2 Mouse / Generic
IRQ12 via SERIRQ
13
No
Math processor
Not applicable
14
Note 1, 2
IDE Controller 0 (IDE0) / Generic
IRQ14
15
Note 1, 2
IDE Controller 1 (IDE1) / Generic
IRQ15
In PIC mode, the PCI bus interrupt lines can be routed to any free IRQ.
Notes
1. Default, but can be changed to another interrupt. If disabled in BIOS setup resource
can be used for another purpose.
2. If the ATA/IDE configuration is set to enhanced mode in BIOS setup (serial ATA and
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