SOMMER SPA-2, Руководство пользователя

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Identify device
The identification of a SDI-12 device is requested with the command
aI!
, with
a
the sensor
address.
EXAMPLE
0I!
Answer
013Sommer USH 140r90 USH-9 <CR><LF>
The answer contains the following information:
0
SDI-12 address
1
SDI-12 version prior to the point
3
SDI-12 version after the point
Sommer Description of the company (6 characters and 2 blanks)
USH
Description of the firmware (5 characters and 2 blanks)
140r90
Firmware version (6 characters and 2 blanks)
SPA-2
Device designation (max. 13 characters)
Acquire measurements
To acquire a measurement from a sensor, two individual SDI-12 commands – trigger a meas-
urement and request measurement values – need to be sent.
EXAMPLE
0M!
Answer:
00084<CR><LF> and 0<CR><LF>
after 8 seconds
0D0!
Answer:
0+2591+706+25.53+0<CR><LF>
The first values in the response to the
aDn!
command is the sensor address.
Trigger measurement
The command
aM!
with sensor address
a
triggers a measurement as in the example below.
The response states the measurement duration and the number of measurement values (see
example below). After completion of the measurement, the device will return an additional
a<CR><LF>
, with
a
the sensor address.
EXAMPLE
0M!
Answer:
00084<CR><LF>
and
0<CR><LF>
after 8 seconds
The answer contains the following information:
0
SDI-12 address
008
Duration of the measurement in seconds
11
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72 Manual