Unable to Set Default Time Reference for Data in 2D Axis System in DIAdem

Issue Details

I am creating a TDMS file in LabVIEW and I am trying to associate two different time channels to their corresponding data channels in the same data group, using the wf_xcolumn and xchannel properties mentioned in the Writing Data-Management-Ready TDMS Files document, but I am not able to have the corresponding time channel be automatically applied to the plot when dragging a data channel into a 2D Axis System in the VIEW panel in DIAdem.

What values should I use in the two properties to correctly associate time and data channels?

Solution

When creating the TMDS file you need to set the wf_xcolumns property with "mixed" as its value at the channel group level, then set the xchannel property in each data channel with the corresponding time channel's name as its value.

In LabVIEW the TDMS Set Properties VI can be used to set the X channel reference:
 
This will allow you to drag only the data channel into the display area and the corresponding time channel will be automatically applied to the plot:
 

Additional Information

The wf_xcolumns property can be included in the channel group level to indicate to DIAdem how many channels will be used as time channel references for the data channels. The values for this property can be one of the following:

• "one": is used when there is only one channel to be used as the time channel reference in the channel group.
• "mixed": is used if there are more than one channel than can be used as a time channel reference within the same channel group.

The xchannel property can be used either in the channel group or channel level, depending on how many time channel references exist within the same channel group. In both cases the value of this property indicates the name of the channel that will be used as the time channel reference.

The following scenarios show possible values for the two properties:

1. The time channel is the first channel in the group, and all other channels in the same group should have an X channel relation to that first channel.

• Use the wf_xcolumns property at group level with a value of "one".

2. The time channel is not the first channel in the group, and all other channels in the same group should have an X channel relation to that channel.

• Use the wf_xcolumns property at group level with a value of "one".
• Use the xchannel property at group level with the name of the time channel to use as its value.

3. Some channels in the group should have an X channel relation, but not necessarily to the same X channel.

• Use the wf_xcolumns property with a value of "mixed".
• In each data channel that will use a given time channel as a time reference, use the xchannel property at channel level with the name of the time channel to use as its value.
• Each data channel can have a different time channel reference, including not having one, when "mixed" is the value of the wf_xcolumns property.