Adding a Warning

Defining custom warnings in an IVI driver allows you to return warnings with a proper COM HRESULT and a properly formatted warning message that can be displayed by various COM-aware IDEs. Internally, the errors and warnings defined for a particular driver are managed as members of a special enum created in the type library. Typically, the enum that houses all of the driver’s error and warning code definitions has a name that ends with ErrorCodesEnum.

To add an IVI-COM warning to a driver

1. From Solution Explorer, double-click the Driver Designer node under the Nimbus node.

2. The Driver Designer opens as a tabbed document window. Select the IVI-COM tab.

3. From the tree view expand the type library node for the instrument-specific hierarchy. This node is named “\<driverName\>Lib”.

4. Right-click on the Warnings node and choose Add Warning.

5. A new warning is added with a default name and the tree node enters edit mode.

6. With the warning node still in edit mode, type the desired name of the warning and hit the Enter key.

   Note

   By convention, warning names start with “S_\<projectName\>”. However, when typing a warning name in the tree view, a shortened form of the name can be used. The “S\<projectName\>_” prefix can be excluded. For example, if the desired warning is S_ACME4321_SWEEP_BUSY, then type only SWEEP_BUSY and the full warning name will be expanded when the Enter key is pressed.

   When choosing a warning name, the following naming rules apply:

   • The name must be unique within the driver.
   • The name must contain only alphanumeric characters and the underscore (_) character.
   • Spaces are not allowed.
   • The name must be uppercase.

7. After the warning is added, the IVI-COM Warning General Editor appears in the right portion of the IVI-COM Designer. See the help topic for that Item Editor for details on defining the warning further.

8. If IVI-C wrapper generation is enabled on the IVI-C Page of the Driver Settings Editor, then an IVI-C warning is automatically created at this time and associated with the IVI-COM warning.

   To view the linked IVI-C warning, right-click the IVI-COM warning, and choose Go to IVI-C Warning.

   To remove the linked IVI-C warning, thereby creating an IVI-COM-only warning, right-click the IVI-COM warning, and choose Delete IVI-C Warning.

See also

• Adding an Error
• Returning Errors from IVI-COM Drivers