Campbell Scientific CR1000 Measurement and Control System - Manual (Page 267)

Section 7. Installation
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also be used in applications where the site cannot be accessed for extended
periods. However, large CF cards do not eliminate the risk of data loss.
1 The CRD: drive is a memory drive created when a CF card is connected to the
datalogger through the appropriate peripheral device. The CR1000 is adapted for
CF use by addition of the NL115 or CFM100 modules. NL115 and CFM100
modules are available at additional cost from Campbell Scientific.
2 CRBasic Editor is included in Campbell Scientific datalogger support software
suites LoggerNet, PC400, and RTDAQ.
7.8.20.2 TableFile() with Option 64 Replaces CardOut()
TableFile() with Option 64 has several advantages over CardOut() when used in
most applications. These include:
• Allowing multiple small files to be written from the same data table so that
storage for a single table can exceed 2 GB. TableFile() controls the size of
its output files through the
NumRecs , TimeIntoInterval , and Interval
parameters.
• Faster compile times when small file sizes are specified.
• Easy retrieval of closed files via File Control (p. 454) utility, FTP, or E-mail.
7.8.20.3 TableFile() with Option 64 Programming
As shown in the following CRBasic code segment, the TableFile() instruction
must be placed inside a DataTable() / EndTable declaration. The TableFile()
instruction writes data to the CF card based on user-specified parameters that
determine the file size based on number of records to store, or an interval over
which to store data. The resulting file is saved with a suffix of X.dat, where X is a
number that is incremented each time a new file is written.
DataTable (TableName,TriggerVariable,Size)
TableFile (FileName...LastFileName)
'Output processing instructions go here
EndTable
For example, in micrometeorological applications, TableFile() with Option 64 is
used to create a new high-frequency data file once per day. The size of the file
created is a function of the datalogger scan frequency and the number of variables
saved to the data table. For a typical eddy-covariance station, this daily file is
about 50 MB large (10 Hz scan frequency and 15 IEEE4 data points). CRBasic
example Using TableFile() with Option 64 with CF Cards (p. 268) is an example
of a micromet application.