waveform in tdms catch

[aartjan]

TDMS is a great addition to Labview, but I want to highlight a tricky limitation: it ignores waveform timestamps! Once you created a new channel by writing a waveform for the first time, it will, only once, write the timestamp property to the channel. After that it will simply add the Y values, ignoring the timestamps.
LV8.5 example attached.

[Herbert Engels]

This behavior as such is intended. If you keep appending waveforms to a channel, you can't overwrite T0. Data you have already written would have a wrong timeline then. If your channel is non-contiguous over time, you'll need to split it up into several groups (for few gaps) or use a timestamp channel (for large numbers of gaps). The "Write Measurement File" Express VI does that automatically if you switch it to "One Header Only" mode. With that said, you can consider it a bug that we don't throw an error instead of appending a non-contiguous piece to a waveform channel, because that does result in wrong data. CAR 4FB7ABWJ.

Herbert

[Coal_Man]

For searchability:

This was reported to R&D (# 4FB7ABWJ) for further investigation.