CR1000 Manual - Campbell Scientific

Section 7. Installation
Table 25. Standard SDI-12 Command and Response Set
Command Name Command Syntax 1 Response 2
Start Concurrent Measurement aC! atttnn
Additional Concurrent
Measurements
Additional Concurrent
Measurements and Request CRC
aC1!
.
.
.
aC9!
aCC1! ... aCC9!
atttnn
atttnn
atttnn
atttnn
atttnn
atttnn
Continuous Measurements aR0! ... aR9! a (formatted like the D commands)
Continuous Measurements and
Request CRC
aRC0! ... aRC9!
a (formatted like the D
commands)
1 If the terminator '!' is not present, the command will not be issued. The CRBasic SDI12Recorder() instruction, however, will still pick up data
resulting from a previously issued C! command.
2 Complete response string can be obtained when using the SDI12Recorder() instruction by declaring the Destination variable as String.
3 This command may result in a service request.
Address Commands
A single probe should be connected to an SDI-12 input when using these
commands.
Address Query Command (!)
Command ! requests the address of the connected sensor. The sensor replies to
the query with the address, a.
Change Address Command (aAb!)
Sensor address is changed with command aAb!, where a is the current address
and b is the new address. For example, to change an address from 0 to 2, the
command is 0A2! The sensor responds with the new address b, or in this
example, 2.
Send Identification Command (aI!)
Sensor identifiers are requested by issuing command aI!. The reply is defined by
the sensor manufacturer, but usually includes the sensor address, SDI-12 version,
manufacturer's name, and sensor model information. Serial number or other
sensor specific information may also be included.
An example of a response from the aI! command is:
013NRSYSINC1000001.2101
where:
Address = 0
SDI-12 version =1.3
Manufacturer = NRSYSINC
Sensor model = 100000
Sensor version = 1.2
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