Campbell Scientific CS650 and CS655 Water Content Reflectometers - Manual (Page 17)

CS650 and CS655 Water Content Reflectometers
SDI-12 communication has the advantage that up to ten probes may be given
different addresses and share a single control port. Another advantage is that
the datalogger programming is much simpler for SDI-12 communication than
RS-232.
The orange Rx wire is only used for RS-232 Tx/Rx
communication, and should be grounded when using SDI-12.
6.3.2 RS-232 Wiring
TABLE 6-2 shows the wiring code for communicating with a CS650 using
RS-232 serial protocol. Device Configuration Utility software uses RS-232 to
communicate with a CS650 through the A200 USB-to-Serial Module. See
Section 6.4, A200 and Device Configuration Utility, for details.
RS-232 communication is not recommended for use with Campbell Scientific
dataloggers because it requires two control ports per CS650 and the
programming is more complicated than for SDI-12 communication.
For RS-232 serial communication with devices other than Campbell Scientific
dataloggers, use the wiring information in TABLE 6-2. Factory default
communication settings are 9600 baud, no parity, 1 stop bit, 8 data bits, and no
error checking.
See TABLE 6-3 for a list of serial commands for the CS650.
TABLE 6-2. CS650 Wiring Code
for RS-232 and A200
Color Function A200 Terminal
Orange RxD Rx
Green TxD Tx
Red Power +12 Vdc
Black Reference G
Clear Shield G
6.4 A200 and Device Configuration Utility
The A200 Sensor-to-PC Interface allows communication between a CS650 and
a PC, allowing sensor settings to be changed through Device Configuration
Utility (DevConfig) software.
6.4.1 Using the A200
6.4.1.1 Driver Installation
If the A200 has not been previously plugged into your PC and your PC
operating system is not Windows 7, the A200 driver needs to be loaded onto
your PC.
NOTE
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