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and use your MIDI card or play back audio via Mona, neither device will
function properly.
Or, maybe you have a SCSI card that had previously been assigned to IRQ
10. The BIOS may now decide to assign IRQ 10 to Mona, and move the
SCSI card to IRQ 9. An interrupt conflict now exists between the SCSI card
and the older MIDI card.
PCI Cards and Interrupt Conflicts
Some plug & play PCI cards can also cause interrupt conflicts when they try
to share an IRQ with another PCI card. Many PCI cards can share an IRQ
with no problems at all, but some just don’t like to share. For example, you
may have a network card installed, and Windows has it configured to use
IRQ 10. Since that is the only card assigned to IRQ 10, Windows assumes
that it is OK to let it share with the next PCI card that comes along.
Consequently, it may assign Mona to share IRQ 10. This network card
happens to be unfriendly and doesn’t like to share, so the next time you try
to use it or Mona, neither device will function properly.
Resolving Interrupt Conflicts
Although there is no way to automatically detect legacy interrupts,
Windows 95/98 and some BIOS’s allow you to reserve specific interrupts
for legacy use. Once an interrupt is reserved it will not be assigned by Plug-
and-Play to another card. Or, if you have a PCI card that doesn’t like to
share you may be able to reassign it to a different IRQ.
The first thing to do if you think you have an interrupt conflict is to
determine which interrupt and which card is causing the problem. To do
this, run the Reporter software that came with your Mona card. For now,
you can skip over the hard disk performance test since it has nothing to do
with interrupts. Once the Reporter has finished the diagnostic routine, it will
provide you with a list of all of the interrupts that Windows 95/98
recognizes are in use and the cards or resources to which they are assigned.
Write down the interrupts that are listed and the devices that are assigned to
them. Pay particular notice to the interrupt to which Mona is assigned.