IRQ Conflicts
Working with
modems introduces a very frustrating topic: IRQs. An IRQ is how a piece
of hardware asks the processor for attention. An IRQ is also called an
Interrupt. When two devices have the same IRQ number, the CPU won’t know
who called it. If the modem takes an IRQ number that is already in use,
then you will have a conflict.
Sound cards frequently cause conflicts
because they can take up to 3 IRQs. The newer modems are Plug and Play.
That means the IRQ is set when you install the modem software and not by
changing the jumpers on the hardware.
You need to be a detective to resolve conflicts. A modem can live on IRQ
2, 3, 4, 5, or 7. Sometimes, a good hardware technician will change the
IRQs to remove the conflicts. When you have a printer, a scanner, a
modem, and a digital camera you can have a recipe for conflicts. The new
Plug and Play standards are supposed to make things easier, at least
that is the theory.
