TDMS wavform store - not working with some data

[george seifert]

I know this was working with LV8.2. I just downloaded 8.2.1 and it's not working. I've enclosed a simplified example. I get error -2513 when I run it.

Possible reason(s):LabVIEW: LabVIEW does not support properties of the specified data type.

First could someone who has 8.2 please confirm that it doesn't give an error?

If I delete array elements 0 and 1 from the "data" control it works. If delete any other combination of elements I get the error. I tried deleting all the elements and created some new waveform elements without attributes and it worked. I can't see anything wrong with the existing attributes. Can anyone see what could be wrong?

Thanks,

George

[Herbert]

George,

I have tried your VI and I can reproduce the problem. The root cause is that the data type of the "NI_ChannelName" property on some of your waveforms is "tag" instead of "string". My first thought would be that the change in data types was introduced by a new driver version. Did you recently update your drivers?

The issue is filed as CAR# 489IR4WJ. There is a workaround, which is converting the property type from tag to string (that's a perfectly valid conversion). It's not nice, but at least it is simple.

http://forums.lavag.org/index.php?act=attach&type=post&id=5459

Sorry for the inconvenience,

Herbert

[george seifert]

QUOTE(Herbert @ Apr 10 2007, 08:29 PM)

George,

I have tried your VI and I can reproduce the problem. The root cause is that the data type of the "NI_ChannelName" property on some of your waveforms is "tag" instead of "string". My first thought would be that the change in data types was introduced by a new driver version. Did you recently update your drivers?

Sorry for the inconvenience,

Herbert

Thanks for the confirmation and the workaround. Yesterday I upgraged to LV 8.2.1 and DAQmx 8.5.

George

I found another workaround. I attached my fix. I was taking the AI.CustomScaleName from the DAQmx Channel node and feeding it directly to the Set Attributes VI. I inserted the convert variant to string and it fixed the problem.

http://forums.lavag.org/index.php?act=attach&type=post&id=5463''>http://forums.lavag.org/index.php?act=attach&type=post&id=5463'>http://forums.lavag.org/index.php?act=attach&type=post&id=5463

George

[Herbert]

QUOTE(george seifert @ Apr 11 2007, 06:28 AM)

I was taking the AI.CustomScaleName from the DAQmx Channel node and feeding it directly to the Set Attributes VI.

I see. I thought you had taken the whole waveform from a DAQmx VI, in which case it should have been a string. We normally coerce tags to strings in most LabVIEW functions, but if they are "hiding" in variant/waveform attributes, that doesn't happen automatically. Need to add that in TDMS Write.

Thanks,

Herbert