Campbell Scientific CR9000X Measurement and Control System - Manual (Page 87)

Section 2. Data Storage and Retrieval
LINE 1: "File Format","Station Name","Logger Model","CPU Serial No.","OS Version",
"Program File","Program File Signature", "File Creation Time"
LINE 2: "Table Name","Record Interval","Data Frame Size","Intended Table Size",
"Validation Stamp","Frame time resolution"
LINE 3: "Field Name","Field Name","Field Name","Field Name","Field Name"
LINE 4: "Field Units","Field Units","Field Units","Field Units","Field Units"
LINE 5: "Process Type","Process Type","Process Type","Process Type","Process Type"
LINE 5: "Data Type","Data Type","Data Type","Data Type","Data Type"
FIGURE 2.4-8. TOB3 file header information
Figure 2.4-9 is an illustration of a TOB3 data file that was created using the
Example Program listed in Example Program 2.4-1.
"TOB3","LogName","CR9000X","1045","CR9000X.STD.05","CPU:Data.C9X",2373,"2009-10-27 16:40:14"
"Temp","10 MSEC","1024","2574034","34004","Sec10Usec"," 0"," 625511219","0677345253"
"TRef","TC_Avg(1)","TC_Avg(2)","TC_Avg(3)","TC_Avg(4)"
"Deg_C","Deg_F","Deg_F","Deg_F","Deg_F"
"Smp","Avg","Avg","Avg","Avg"
"IEEE4l","FP2","FP2","FP2","FP2"
(data lines are binary and not directly readable )
FIGURE 2.4-9. TOB3 data file example
TOB3 data are stored in fixed size “frames” that generally contain a
number of records. The size of the frames is a function of the record size.
The frames are time stamped, allowing the calculation of time stamps for
their records. If there is a lapse in periodic interval records that does not
occur on a frame boundary, an additional time stamp is written within the
frame and its occurrence noted in the frame boundary. This additional time
stamp takes up space that would otherwise hold data.
When TOB3 files are converted to another format, the number of records
may be greater or less than the number requested in the data table
declaration. There are always at least two additional frames of data
allocated. When the file is converted these will result in additional records
if no lapses occurred. If more lapses occur than were anticipated, there
may be fewer records in the file than were allocated.
2-15