Legacy: Resolving Resource Conflicts in Windows NT
All GPIB boards can make use of three different kinds of resources in your computer: base I/O address (a.k.a. input/output range), interrupt request (IRQ), and direct memory access (DMA). The base I/O address is always required, because your computer keeps track of "where your board is" with this address. The other two resources, IRQ and DMA, are used to transfer data into system memory. DMA is not required by a GPIB board to work, but your GPIB board must have an IRQ in order to work in Windows NT.
Windows NT Diagnostics
Windows NT provides a convenient utility called Windows NT Diagnostics to determine which devices and drivers are using which resources:
- Go to Start » Programs » Administrative Tools (Common) » Windows NT Diagnostics to launch Windows NT Diagnostics.
- Click on the Resources tab to get to a screen like this:
At the bottom of the window, you can choose:
IRQ to view which interrupt resources are already in use
I/O Port to view which base I/O addresses are already in use
DMA to view which DMA channels are already in use
- If a resource is listed, then it is in use. Look for resources that are NOT listed to see if they are available.
For example, in the above image IRQs 1, 4, 5, 6, 9, 10, 12, 14, and 15 are listed,
so they are in use. IRQs 2, 3, 7, 8, 11, and 13 are not listed, so they are
potentially available.
- Copy down several alternatives for each hardware resource, because even though a resource setting is shown as NOT being in use by Windows NT Diagnostics, there still exists the possibility that Windows NT is not reporting its usage correctly.
Some devices (such as network cards) use more resources than they admit to using.
If your GPIB Troubleshooting Wizard told you that your GPIB board has a resource conflict, then the device your board is in conflict with may not be listed here.
Other Troubleshooting Tips
- The NI-488.2 Troubleshooting Wizard is usually accurate in alerting you to the nature of any resource conflicts in your system. The first thing to do is to change the offending resource value to one that does not conflict with any other devices. (Setting the DMA to none is also very helpful, if the problem is an IRQ conflict.)
If that doesn't work, then try removing other boards from your computer, until the resource conflict is resolved.
- Windows NT Diagnostics indicates that the resource in conflict is available.
If the NI-488.2 Troubleshooting Wizard told you that you had a base I/O address
conflict, but Windows NT Diagnostics says the resource is available, then you have
either configured your base I/O address incorrectly, or Windows NT may be unable to
detect other, legacy (i.e., non-plug and play) hardware in your computer that may be
causing the resource conflict with your GPIB board. Change the base I/O address of
your GPIB board to the next available address.
