Legacy: Resolving Resource Conflicts in Windows 98/95
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. These resource types are not required by a GPIB board to work, but they make for more efficient data transfer.
Windows 98/95 provides a convenient utility called the Device Manager to determine which devices and drivers
are using which resources:
- Go to Start » Settings » Control Panel to launch the Control Panel window, and then double-click on the System icon. In the System Properties window, click on the Device Manager tab at the top of the window.
- Click on the + symbol next to National Instruments GPIB Interfaces to display a list of GPIB boards intalled in your computer.
Windows 98/95 cannot detect legacy (i.e., non-plug and play) GPIB boards. They must be added using
Start » Programs » National Instruments NI-488.2 » Add GPIB Hardware.
- If the operating system has detected a resource conflict, it will indicate this with a special symbol (a black exclamation mark within a yellow circle) next to the name of the device with the resource conflict:
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, this symbol may or may not
be present. See below.
- Single-click on the device with the resource conflict to highlight it and then click on the Properties button at the bottom of the window. This will bring up the Properties window for your GPIB board. Select the Resources tab. You should see a screen similar to the one below:
- Deselect the Use automatic settings checkbox, and single-click on the resource with the conflict to highlight it.
You may need to change the entry in the Setting based on menu ring to a different basic
configuration, in order to disable the use of certain resources. The basic configurations range from a
"base I/O address only" setup to various combinations of base I/O address, IRQ, and DMA. (Note: some
devices only have one basic configuration.)
- Click on the Change Setting... button to bring up the editing window for that resource. You will be able to cycle through the available resource settings for your system. If Windows 98/95 is aware of any devices that are already using that setting, you will be informed of this in the Conflict information area at the bottom of the resource editing window.
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, (see the page on Finding Available Resources). If that doesn't work, then try removing other boards from your computer, until the resource conflict is resolved.
- The Device Manager does not show a resource conflict symbol.
If the NI-488.2 Troubleshooting Wizard told you that you had a base I/O address conflict, but the Device
Manager does not show an exclamation mark, then you have either configured your base I/O address
incorrectly, or Windows 98/95 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 (see the page on Finding