Troubleshooting
PEB-2770/2780VG2A User’s Manual
5-3
Improper disable operation
There are too many occasions where users disable a certain device/feature in one
application through BIOS setting. These variables may not be set back to the original
values when needed. These devices/features will certainly fail to be detected.
It is also very common that users would like to disable a certain device/port to
release IRQ resource. A few good examples are
A quick review of the basic IRQ mapping is given below for your reference.
IRQ#
Description
IRQ #0
System Timer
IRQ #1
Keyboard Event
IRQ #2
Usable IRQ
IRQ #3
COM2
IRQ #4
COM1
IRQ #5
Usable IRQ
IRQ #6
Diskette Event
IRQ #7
Usable IRQ
IRQ #8
Real-Time Clock
IRQ #9
Usable IRQ
IRQ #10
Usable IRQ
IRQ #11
Usable IRQ
IRQ #12
IBM Mouse Event
IRQ #13
Coprocessor Error
IRQ #14
Hard Disk Event
IRQ #15
Usable IRQ
It is then very easy to find out which IRQ resource is ready for additional peripherals.
If IRQ resource is not enough, please disable some devices listed above to release
further IRQ numbers.