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Assay and Acquisition of Radiopure Materials

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vetoshield:daq:datafiles

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vetoshield:daq:datafiles [2013/02/21 13:22] – created wgilbertvetoshield:daq:datafiles [2013/02/21 15:14] (current) – wgilbert
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 The datafiles are named with the date and time of creation in the filename in YYMMDDHHMMSS format. This avoids overwriting, and puts the File D/T where it won’t be overwritten by the operating system when the file is copied or opened and inadvertently saved. The filenames also sort nicely in a directory listing in this format. File size is limited to 100MB and a new file is started when this limit is exceeded. At max data rate, 250,000 triggers/sec, it takes about 7 seconds to fill a 100MB file. Sustained high rates are not normal, however, and only occur during testing or fault conditions. The datafiles are named with the date and time of creation in the filename in YYMMDDHHMMSS format. This avoids overwriting, and puts the File D/T where it won’t be overwritten by the operating system when the file is copied or opened and inadvertently saved. The filenames also sort nicely in a directory listing in this format. File size is limited to 100MB and a new file is started when this limit is exceeded. At max data rate, 250,000 triggers/sec, it takes about 7 seconds to fill a 100MB file. Sustained high rates are not normal, however, and only occur during testing or fault conditions.
  
-A block of information is prepared and prepended as a header when a file is opened, and appended as a footer when the file is  closed. It take the following form: +A block of information is prepared and prepended as a header when a file is opened, and appended as a footer when the file is  closed. It takes the following form: 
-  +
   * block of 9 U32 xFFFFFFFF flag integers   * block of 9 U32 xFFFFFFFF flag integers
   * U32 Endian indicator xFFFF0000 (if endian-ness of a system reading the file is wrong, it would come back x0000FFFF )  *   * U32 Endian indicator xFFFF0000 (if endian-ness of a system reading the file is wrong, it would come back x0000FFFF )  *
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       end of character string info       end of character string info
   * block of 10 U32 xFFFFFFFF flag integers   * block of 10 U32 xFFFFFFFF flag integers
 +
 + \\
 +
 +**Screenshot of header portion of data file produced under test settings shown in [[Vetoshield:daq:ModifyCfg FP|Modify Config Front Panel]]**
 +
 +see http://mh-nexus.de/en/hxd/ for the **HxD** hex viewer/editor used to get this) 
 + 
 +{{vetodaq:hexed_datafile_ssht.png}}
vetoshield/daq/datafiles.1361474562.txt.gz · Last modified: 2013/02/21 13:22 (external edit)

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