OTT Pluvio 2 S, Operating Instructions Manual

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6 SDI-12 commands and responses
6.1 Basic commands
All SDI-12 basic commands are implemented in the OTT Pluvio
2
S. The following SDI-12 basic commands are relevant for the
operation of the OTT Pluvio
2
S.
Conventions applicable to measured value formats:
p – Sign (+,–)
b – Number ahead of the decimal point (Output without leading zeros)
e – Number after the decimal point
Note: Each aM! command resets the total measured values Accu RT-NRT and Accu NRT to zero!
Command Response Description
a! a<CR><LF> Acknowledgment active
a – sensor address; factory setting = 0
aI! allccccccccmmmmmm …
… vvvxxxx<CR><LF>
Send identification
a – sensor address
ll – SDI-12 protocol version
cccccccc – manufacturer identification (company name)
mmmmmm – sensor identification
vvv – sensor version (firmware)
xxxxxx – serial number
OTT Pluvio
2
S response = 013OTT HACHPLUV2S100xxxxxx
aAb! b<CR><LF> Change sensor address
a – old sensor address
b – new sensor address
?! a<CR><LF>
Query sensor address
(not possible at SDI-12 bus operation)
a – sensor address
aM! / aM1! atttn<CR><LF> Start measurement
a – sensor address
ttt – time in seconds until the sensor
has determined the measurement result
OTT Pluvio
2
S response = 000
n – number of measured values
OTT Pluvio
2
S response = 9 to aM
3 to aM1!
aMC! / aMC1! atttn<CR><LF> Start measurement and request CRC (Cyclic Redundancy
Check). For details, see command aM! . The responses to
the D0! … aD2! commands in this case are extended by
a CRC value (example):
a<value1><value2><value3><CRC><CR><LF>
aC! / aC1!
atttnn<CR><LF>
Start concurrent measurement (simultaneous measurement
with multiple sensors on one bus line). For details see com-
mand aM! . The number of measured values in the response
to this command is two-digit: nn = 09 or 03.
aCC! / aCC1! atttnn<CR><LF> Start concurrent measurement (simultaneous measurement
with multiple sensors on one bus line) and request CRC
(Cyclic Redundancy Check). For more details, see command
aM! . The number of measured values in the response to
these commands is two-digit: nn = 09 or 03.
The responses to the D0! … aD2! commands in this case
are extended by a CRC value (example):
a<value1><value2><value3><CRC><CR><LF>
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