OTT Pluvio 2 S - SDI-12 Commands and Responses; Basic SDI-12 Commands

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
l
l – 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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