FTS DTS-12, Руководство пользователя

Страница: 23 / 32

700-DTS-12 Rev. 28 - 16 Apr 2020 Page 19/28
Chapter 3 SDI-12 COMMANDS
3.1 Notation for SDI-12 Commands
SDI-12 commands are strings of characters sent to the SDI-12 device. The format of the strings is
important, and to specify the format of SDI-12 commands different typefaces are used. All
commands to and the replies from the device are represented in a mono-spaced font. Different
parts of a command are represented with variants on this text format
Item Explanation Font Text representation
Command literal Part of a command that must be
reproduced literally as it appears
Bold X
Command
parameter Part of a command that must be
filled in with an appropriate
value Italic data
Address part of
command First character of command
(except Address Query). Valid
values 0-9, a-z, A-Z. Italic a
The DTS-12 uses the standard SDI -12 Commands and protocols
5
which makes it compatible for use
with DCP’s or transmitters.
Note the following:
• the “ a ” in each command should be replaced with the sensor address number
•
every command must terminate with an exclamation mark ( ! )
•
a C
following an M command requests a CRC code in the data return. The CRC is added at the
end of the message for commands with CRC
•
the measurement command must be followed by a Send Data command ( a D0! ) to view the
data
•
Continuous measurement commands (R commands) will not return data as the DTS12 is not
a continuous measurement sensor.
•
Response to commands that are not supported by the sensor will be the sensor address
followed by a series of zeroes
3.1.1 General SDI-12 Commands
General SDI-12 commands are used for housekeeping issues such as device address configuration,
device identification and confirmation of device communications. General SDI-12 version 1.3
commands are as follows
5
In accordance with SDI-12 Specification, version1.3 http://www.sdi-12.org