Recover TDM header file

[GReaper]

Hello all,

I have a DAQ program that has been running for a while now and just recently, on one test, after closing the DAQ the program hung.  (still not sure why)  The end result apears to be the TDX data file is intact but the TDM header file (xml description of the data) was trashed.

Can anyone give me any ideas on how to access the TDX file and recover the lost test? 

I have attempted to use/modify the TDM for a test run just prior (exact same set up) with limited success.  I can't seem to adapt it to read past the time of the test it was saved for.

Anywho, thanks in advance for any help.

Cheers,

[Vivek_N]

Hello Greg,

The TDM file must have become corrupt. What exactly happens when you try to use the TDM file? What are you able to read from it and what are you not able to read? Also, what does the TDM header file contain? Are you able to open it?

[GReaper]

Hi Vivek,

The TDM is definitely toast.  It is there but is empty (size 0 bytes).  The associated TDX is there with a size of 12,134 KB so I'm assuming I have data in there.

When I copied the previous TDM to do surgery on it to make it work for the TDX with the corrupt TDM I have some success.  The obvious fix is changing the URL tag 13 lines in.  That gets me to start reading just the first bit of data.  The test I steal the header from tho is only a few tens of seconds long while the corrupt test ran for 40 - 50 minutes.  So there is some voodoo needed to define how many points are there.  I see a length field in the <usi:include> tag and a <number_of_rows> tag down in the <submatrix> tags that would appear also to need adjusted.  However, jacking up those numbers eventually causes a crash.  I think this *may* be due to the <minimum> and <maximum> tags in the <tdm_channel> sections.  And that is as far as I have gotten. 

Could I just get away with trying to reading this as 32 channels of interleaved binary data?