User Manual

where a is the sensor address (“0-9”, “A-Z”, “a-z”, “*”, “?”) and C is an upper-case ASCII character.
For example (0 is the address):
Command
Sensor Response
0C0!
000101<cr><lf>
0D0!
0+2000.0<cr><lf>
0C1!
000101<cr><If>
0D0!
0+400.0<cr><If>
0C2!
000101<cr><lf>
0D0!
0+2000.0<cr><lf>
0C3!
000101<cr><If>
0D0!
0+2000.0<cr><If>
where 2000.0 is µmol m
-2
s
-1
and 400.0 is mV.
Change Sensor Address: aAb!
The change sensor address command allows the sensor address to be changed. If multiple SDI-12 devices are on
the same bus, each device will require a unique SDI-12 address. For example, two SDI-12 sensors with the factory
address of 0 requires changing the address on one of the sensors to a non-zero value in order for both sensors to
communicate properly on the same channel:
Command
Response
Description
aAb!
b<cr><lf>
Change the address of the sensor
where a is the current (old) sensor address (“0-9”, “A-Z”), A is an upper-case ASCII character denoting the
instruction for changing the address, b is the new sensor address to be programmed (“0-9”, “A-Z”), and ! is the
standard character to execute the command. If the address change is successful, the datalogger will respond with
the new address and a <cr><lf>.
Send Identification Command: aI!
The send identification command responds with sensor vendor, model, and version data. Any measurement data
in the sensor's buffer is not disturbed:
Command
Response
Description
"aI!"
a13Apogee SQ-421vvvxx…xx<cr><lf>
The sensor serial number and other identifying values are
returned
where a is the sensor address (“0-9”, “A-Z”, “a-z”, “*”, “?”), 421 is the sensor model number, vvv is a three
character field specifying the sensor version number, and xx...xx is serial number.