Campbell Scientific Wireless Sensor Network (CWB100, CWS220, and CWS900) - Manual (Page 40)

Wireless Sensor Network
discovered. This can make it difficult to use specific values in the datalogger
program because of uncertainty as to which position in the array the value of
interest will be assigned. The CRBasic instruction ArrayIndex may be used to
reference values returned by wireless sensors regardless of where those values
are in the destination array. See Section 4.3 for details on ArrayIndex.
4.2.2 Field Names
Field names are generated or learned by the base and are provided to the
datalogger for the purpose of generating table definitions. The configuration
string is used as a starting point for field name generation. If the configuration
string does not fully specify field names, default names with a serialize root
name “ _Fn” are generated by the base. Later, as new sensors are discovered,
the generated names are modified by field names learned from the sensor with
the “_Fn” portion of the name replaced by the field name learned from the
sensor.
For example, before discovery, a generated field name might be:
"CWS650__F3", then after discovery, this may change to "CWS650_BatV"
where "BatV" was the field name provided for the third field by the sensor.
If a sensor name is not provided by the configuration string, then the sensor
name learned from sensor discovery will be used to name the sensor. These
auto-discovered sensor field names are added to the end of the list of field
names until all available space in the Destination Array is consumed.
These default sensor field names are shown in Wireless Sensor Planner,
Network Planner, and DevConfig software. Descriptions of the default sensor
names are found in Appendix B.
4.2.3 Status Monitoring
All CWS sensors generate both measurement and status values. The status
fields (usually battery voltage, module temperature, and RSSI) are always
included as the last three fields returned by the sensor. Including status
information along with measurement data from each sensor is the easiest way
to manage status information. It is recommended that status data be recorded
by the datalogger to assist in data analysis and troubleshooting.
If status data is not desired, then specify only the measurement fields in the
configuration string. If the configuration string specifies fewer values than are
returned by the sensor, only as many values as are specified will be saved in
the Destination Array.
For example, CWS650_1 returns 7 values, including 3 status values. To ignore
the status values use a configuration string similar to:
AF6345bd3404 CWS650 4.
Limiting the number of fields to 4 means the first 4 measured values will be
stored in the destination array and the last 3 status values will not.
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