Tech Note 157 Detail

PCI bus IRQ conflict

Affected Products:

CI-7565 ScienceWorkshop 750 Interface

Problem/Symptom:
I am installing the 750 interface with SCSI card on my computer but the IRQ I need to use is being held for PCI steering. What can I do?

PASCO Solution:
If you have checked the IRQ settings in the device manager and there are no other available IRQs between 09 and 12, you may be able to remove the IRQ Holder for PCI Steering from the IRQ you need.

The PCI bus reserves several IRQ numbers at start-up. If your computer has PCI slots, you may have to make a change to the BIOS. To access the settings, hold down the delete key at start-up or on some computers you will need to hold down the F2 key.

The menu options will vary from computer to computer. However, there should be a way in your BIOS to prevent the computer from taking the IRQ that the SCSI card is using. In the menus, find the settings for the PCI controls. Look for an option that manually or automatically allocates interrupt numbers to the PCI slots.

Then, change the settings to free the IRQ used by your SCSI card. Exit the BIOS and save the new settings. Your computer will then continue to boot.

If the interface is still not recognized by the computer and you do not wish to use a COM port connection, you should continue with the troubleshooting tips.

Creation Date: 01/1/2000
Last Modified: 01/1/2000
Mod Summary: