Design Analysis H-350XL, Руководство пользователя, Страница: 136 / 272

14-20 SDI-12 Operations
XL™ Series
14.7.5 Measure Command
The Measure Command causes a measurement sequence to be performed. Data values generated
in response to this command are stored in the sensor's buffer for subsequent collection using "D"
commands. The data will be retained in the sensor until another "M" or "V" command is
executed.
Command Response Description
------------- ---------------------- ------------------------------------
"aM!" "atttn<cr><lf>"
Initiate measurement
"aM1!" "atttn<cr><lf>"
Additional measurement commands
Where:
a Is the sensor address ("0" to "9", "A" to "Z", or "*").
M (or M1) are upper-case ASCII characters.
ttt Is a three digit integer (000-999) specifying the maximum time, in seconds, the
sensor will take to complete the command and have measurement data available
in its buffer.
n Is a single digit integer (0-9) specifying the number of values that will be placed in
the data buffer. If "n" is zero (0), no data will be available using subsequent "D"
commands.
Upon completion of the measurement, a service request "a<cr><lf>" is sent to the data recorder
indicating the sensor data is ready. The data recorder may wake the sensor with a break and
collect the data any time after the service request is received or the specified processing time has
elapsed.
The following table lists the measure commands supported by the W
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LOG H-350XL™ and
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the responses from the sensor.