Campbell CS650, User Manual

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Appendix D. SDI-12 Sensor Support
D-3
to an aD0! command is 35 characters. If the number of characters exceed the
limit, the remainder of the response are obtained with the subsequent aD1!
command.
D.2 Changing the SDI-12 Address Using Terminal
Emulator and a Datalogger
Up to ten CS650’s or other SDI-12 sensors can be connected to a single datalogger
control port. Each SDI-12 device on the same control port must have a unique
SDI-12 address. The CS650 supports addresses of 0-9, a-z, and A-Z.
The factory-set SDI-12 address for the CS650 is 0 when the probe is ordered with
the –DS option or the last digit of its serial number when ordered with the –VS
option. The CS650 SDI-12 address is changed by issuing the
aAb! command
where a is the current address and b is the new address. The current address can
be found by issuing the ?! command.
The easiest way to change the address on a CS650 sensor is with DevConfig and
an A200 Sensor to PC Interface as described in Section 8.1 , A200 and Device
Configuration Utility
(p. 12)
. However if an A200 is not available, it is possible to
change the address by connecting a single CS650 to an SDI-12 compatible control
port on a datalogger and utilizing SDI-12 transparent mode to send commands
directly to the sensor.
D.2.1 SDI-12 Transparent Mode
System operators can manually interrogate and enter settings in probes using
transparent mode. Transparent mode is useful in troubleshooting SDI-12 systems
because it allows direct communication with probes. Datalogger security may
need to be unlocked before transparent mode can be activated.
Transparent mode is entered while the PC is in telecommunications with the
datalogger through a terminal emulator program. It is easily accessed through
Campbell Scientific datalogger support software, but is also accessible with
terminal emulator programs such as Windows HyperTerminal. Datalogger
keyboards and displays cannot be used.
The terminal emulator is accessed by navigating to the Datalogger menu in
PC200W , the Tools menu in PC400 , or the Datalogger menu in the Connect
screen of LoggerNet .
The following examples show how to use LoggerNet software to enter transparent
mode and change the SDI-12 address of a CS650 sensor. The same steps are used
to enter transparent mode with
PC200W and PC400 software after accessing the
terminal emulator as previously described.