Capturing Calls to IVI Class Drivers

To view calls to IVI class drivers, you must enable capturing. When you launch NI IO Trace, capturing is disabled. To enable capturing, use one of the following methods:

• Select IO Trace»Start Capture.
• Click the blue arrow on the toolbar.
• Press <F8>.

After you enable capturing, run your application then return to NI IO Trace to view the captured calls. For a complete description of how to use NI I/O Trace, refer to the NI IO Trace Windows Help. To view the NI IO Trace help, select Help»Help Topics. The following figure shows calls to the IviScope class driver that NI IO Trace captured.

NI IO Trace displays the name of each class driver function call that it captures. For each function call, NI IO Trace displays the values of the input and output parameters. You can configure NI IO Trace to display the following details about the function call:

• Number
• Description
• Status
• Time
• Process ID
• Thread ID

If a function returns an error, NI IO Trace highlights the function call in red. If you enable interchangeability checking, NI IO Trace highlights the functions that report interchangeability warnings in blue.