Overview
These example VIs show how to use an NI oscilloscope to verify the synchronization of two NI waveform generator modules when using NI-TClk.
Description
Verify NI-FGEN Synchronization.vi
This VI opens two NI-FGEN sessions to the two NI waveform generator modules, and configures them to generate an 80 MHz sine wave (the max frequency for a PXIe-5433). Then, an NI-SCOPE session is opened to the NI oscilloscope module, which is configured with settings to accurately capture the signals generated by the waveform generators. NI-TClk is used to synchronize and initiate generation on the waveform generators. The VI resamples the acquired data to a dt of 1 picosecond, and uses the Basic Level Trigger Detection VI to find the zero crossings and compare them.
Verify NI-FGEN Synchronization Repeatability.vi
This VI is similar to the previous VI, but it performs a more sophisticated phase measurement with the Extract Single Tone Information VI to compute skew. It also demonstrates how to minimize synchronization skew and jitter with manual TClk adjustment by setting the Absolute Delay property with NI-FGEN.
Hardware and Software Requirements
- Hardware
- Two PXIe-5433 waveform generator modules
- PXIe-5113 oscilloscope module
- PXI chassis and controller
- Matched length coaxial cables to connect the two waveform generators to the channel inputs on the oscilloscope
- SMA / BNC adapters as needed
- Software
- LabVIEW 2023 Q1 or newer
- NI-FGEN 2023 Q1 or newer
- NI-SCOPE 2023 Q1 or newer
Steps to Implement or Execute Code
Download and run the attached VIs.
Using two identical coaxial cables with the exact same length is required to get accurate results. This is due to the effects of propagation delay.
The results of the skew calculation may be affected by inaccurate DC gain and offset. All of the modules should be properly calibrated to ensure DC accuracy. The attached VI has an option to run Self Calibrate as part of the verification procedure.
Additional Information or References
