[ILUG] Problems with IRQ (SuSe 6.3)

[Wynne, Conor]

Yo,

For interrupt sharing, both the driver and the controller (nic + modem) have
to support interrupt sharing. 

As a rule of thumb, only the same cards with the same driver can safely
share interrupts. 

Yes, PCI cards can tolerate sharing in the manner below, but sharing ISA and
PCI, ughhh, steer clear my friend. 

ISA bus is what 8Mhz, PCI is 33Mhz , also nic's generate massive amounts of
interrupts per second, and I hear tell that ISA ones are worse!

I usually reserve the slow interrupts for slow cards, and fast for fast.
Check google for the ones. 

I reserve, IRQ's 3,4,7,9 all for legacy ISA. 
Also beware that some system boards share interrupts among pci slots so
check you mobo manual. My ABIT shares 3 + 4 as far as I can remember - which
incidentally caused major sound issues as it was shared with my 3com PCI
nic. 

Either the nic didn't work or the soundlag was shite. Moved slot and all is
fine.  

My 0.78 euros. 

CW


-----------------------------------
On Mon, Oct 08, 2001 at 01:13:55AM -0700, Ramon Diaz wrote:

> I recently installed SuSe 6.3 (kernel 2.2.13) in a
> spare box, and I have a conflict with my IRQ's. Both
> the network card and the modem have IRQ 10.

If they're both PCI devices then it shouldn't matter because the PCI design
allows for shared interrupts. I'd have a gut feeling that sharing IRQs on a
modem and network card wouldn't be absolutely the best configuration but
should work. 

> Is there a way either through the GUI or using the
> actual terminal, to modify the IRQ?

Some PCI BIOSes will allow you to manipulate assignment of IRQs to slots.

If OTOH one or both of your devices is ISA you'll have to modify one of them
by using either jumpers or a program delivered with the hardware to change
the IRQ it uses, and if you're using software, it's likely that you'll need
to remove one of the devices while programming the other.


Niall