Campbell Scientific Sentek EnviroSCAN EasyAG SDI-12 Manual v 3.4 - Manual (Page 14)

EnviroSMART & EasyAG SDI-12 Probe Manual
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Command Response
aM! a0139
The response indicates that 9 soil moisture values will be available within a time of 13 seconds. After
approximately 10 seconds the probe will issue a Service Request (a, where “a” is the probe
address). The controlling device will then issue Send Data commands (aDn!) to read the values.
Command Response
aD0! a+001.0000+001.1234+000.0200
aD1! a+000.1234+000.0000+123.1234
aD2! a+010.1200+000.1243+044.8750
If there are more than 9 soil moisture values, a further Start Measurement command (aM! or aMn!)
must be issued.
Command Response
aM1! a0117
The response indicates that another 7 soil moisture values will be available within a time of 11 seconds.
After approximately 8 seconds, the probe will issue a Service Request (a, where “a” is the
probe address), and the controlling device will then issue Send Data commands (aDn!) to read the
values.
Command Response
aD0! a+002.0010+003.1234+001.0200
aD1! a+011.1234+001.0100+011.3344
aD2! a+012.0230
Note: The Send Data commands (aDn!) must be issued in increasing order.
Salinity Values (aM2! and aM3!)
The Start Measurement command (aM! or aMn!) allows up to nine(9) values to be returned. As it is
possible to have up to sixteen(16) salinity values from the EnviroSMART SDI-12 probe interface,
two(2) Start Measurement commands (aM! or aMn!), “aM2!” and “aM3!” are required. The Send Data
command (aDn!) may return up to three(3) values.
Command Response
aM2! a0239
The response indicates that 9 salinity values will be available within a time of 23 seconds. After
approximately 21 seconds the probe will issue a Service Request (a, where “a” is the probe
address). The controlling device will then issue Send Data commands (aDn!) to read the values.
Command Response