Timing Errors

If your application fails, but the same calls issued interactively in the Interactive Control utility are successful, your program might be issuing the NI-488.2 calls too quickly for your device to process and respond to them. This problem can also result in corrupted or incomplete data. This is only a problem with older, non-standard GPIB devices.

To start Interactive Control on Linux, open a terminal and enter the following command:

gpibintctrl

To start Interactive Control on macOS, double-click on Applications»National Instruments»NI-488.2»Interactive Control.

A well-behaved IEEE 488 device does not experience timing errors. If your device is not well-behaved, you can test for and resolve the timing error by single-stepping through your program and inserting finite delays between each NI-488.2 call. One way to do this is to have your device communicate its status whenever possible. Although this method is not possible with many devices, it is usually the best option. Your delays will be controlled by the device and your application can adjust itself and work independently on any platform. Other delay mechanisms probably exhibit differing behaviors on different platforms and thus may not eliminate timing errors.

The NI-488.2 Troubleshooting Wizard helps you troubleshoot any problems with your NI-488.2 software. This wizard verifies that your GPIB hardware and the NI-488.2 software are installed correctly and working properly.