User’s Manual
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An IRQ number is automatically assigned to PCI expansion cards after those used
by Legacy and PnP ISA cards. In the PCI Bus design, the BIOS is automatically
assigned an IRQ to a PCI slot that has a card in it which requires an IRQ. To install
a PCI card, you need to set the correct "ADSEL" and "INT" (interrupt) assignment.
Please refer to "Chapter 2-5" Installing a Riser Card for detail assignments.
IRQ
Status Assignment
0 Used
Timer
1 Used
Keyboard
2 Used
Second
8259
3 Used
COM2
4 Used
COM1
5 Used
COM3
6 Used
Floppy
Disk
7 Used
LPT1
8 Used
RTC
9 Used
LPT2
10 Used
COM4
11
Used LAN Adapter (on board)
12 Used
PS/2
Mouse
13 Used
Coprocessor
14
Used Hard Disk (IDE 1)
15
Used Reserved (IDE 2)
2-8. Assigning DMA Channels for ISA Cards
Since ISA cards, both Legacy and PnP may also need to use a DMA (direct
memory access) channel, DMA assignments for this motherboard are
handled the same way as the IRQ assignment process described above. You
can select a DMA channel in the PCI and PnP configuration section of the
BIOS setup utility. In the BIOS setup, you should choose "Yes" for those
IRQ's and DMA's you wish to reserve for Legacy cards.
