10-02-2024 07:54 AM
Good afternoon,
I'm working on a project where the system is implemented in a cRIO-9068 with 8 modules using Labview2019.
I need to acquire different modules at different data rate, at 10 kHz and 100 Hz using a FIFO. I set the acquisition with the TDMS and it is working at high data rate but the problem is related to the inclusion of a timestamp of each data acquired. I tried different methods but it seems as if the file cannot write time at the same speed as it writes data.
I can't use the function daqmx because it is not supported by my cRIO.
Thank you in advance.
10-02-2024 06:01 PM
I recommend NI CompactRIO Waveform Reference Library
10-03-2024 10:18 AM
Thanks for the answer! I'll have a look to the new functions.
By the way I have been able to add the starting moment of the acquisition with the wf start time in the tdms format. Do you know if there is a way to add also the wf end time? This would be a kind of work-around solution because I know the acquisition rate.
Thank you.
10-04-2024 04:08 AM
Use the waveform data type to include t0, dt and other attributes like the channel name. This replaces your "to dynamic data".
This will set the wf_start_time and wf_increment in the TDMS file.(See here: TDMS File Format Internal Structure#Predefined Properties)
The waveform attributes will be written as TDMS properties.
write waveform to tdms
10-04-2024 07:29 AM
@Giuu wrote:
Thanks for the answer! I'll have a look to the new functions.
By the way I have been able to add the starting moment of the acquisition with the wf start time in the tdms format. Do you know if there is a way to add also the wf end time? This would be a kind of work-around solution because I know the acquisition rate.
Thank you.
You can't define end time directly. The end time is t0 + dt*([number of elements in Y] - 1). See Using the Waveform Data Type in LabVIEW to understand more about this data type.