Resolving IRQ Assignment

[kevmove02]

Hey Everyone! Haven't posted in awhile, but have been lurking. I wanted to share an experience and get some advice.

I recently inherited a Toshib A25 laptop that is quite a bit faster than the on I had. It's 2.66ghz with 2 gigs of Ram. My dream of finally be able to run Cubase and other programs more efficiently were about to come true until I encountered a small glitch: all of my USB device were being assigned to the same IRQ (interrupt request)! This caused all kinds of interrupts of my audio stream. To make matters worse, I can't seem to isolate my audio interface (Session IO) on its own IRQ. I did some research and discovered that Windows XP sp3 automatically configures itself for ACPI. I tried switching to a Standard PC in the Device Manager, but it looks like all of the audio devices are still being assigned to same IRQ. Any ideas on how to manipulate the system into assigning a different IRQ to my audio interface? I already change the usb ports that I plug into and I tried only connecting 1 device at a time. I also need to get my ext hard drive to have a IRQ different from the audio interface. Thanks!

[Audio~Geek]

With a laptop there is probably nothing you can do.
Moving to a firewire interface may be your only hope, you will want your HD to be firewire.

on a desktop IRQ is usually fixed by moving the component to a different slot, crossing your fingers and a short pray.

You may be able to manually change IRQ assignments through your BIOS, probably not though.

I recently went through some IRQ headache too. I ended up buying a PCI express Firewire card to get around the PCI slots sharing IRQ with video and network.

[spaceatl]

USB is interrupt driven and the host controller has only one interupt because it is a serial bus...You need more host controllers to get more IRQS.... I suppose a separate PCMCIA card might help but them you are at the whims of the laptop and windows as to whether the IRQ used by your current host controller would be shared with the new one...It seems likely it would get a new one...

[fmw]

In addition to what the others have said, I'll let you know that processor interrupts are going to occur regardless of which controller calls them. In other words, if you could reassign IRQ's it wouldn't stop the interrupts. Nothing that uses USB will. Firewire is the way to go in your case.