Xylem SDI-12 RADAR - Manual (Page 21)

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”, “ C”, or “V” command is
executed.
Command response Description
“am!” “atttn” initiate measurement
where:
a is the sensor address (“0-9”, “a-Z”, “a-z”, “*”, “?”).
m is an upper-case aSCii character
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.
SDI-12 Command & Response
19
The radar supports the following SDi-12 commands:
Standard Commands:
am! make measurement
am1! make Noaa measurement
am2! make 1 minute average measurement
am3! make 15 second average measurement
aD0! Send Data
aV! Verify
aI! Send identification
a! Send acknowledge
aan! Change address
Extended Commands:
aXrs! read Slope
aXWsnn! write Slope
aXrO! read offset
aXWOnn! write offset
aXrPm! read Power mode (0=Sleep, 1=Fast measure)
aXWPmn! write Power mode (0=Sleep, 1=Fast measure)
aXWnm! write the number of measurements used in the fast mode “am1” command
aXrnm! read the number of measurements used in the fast mode “am1” command
aXTesT! Displays the current settings, then displays data at a fast rate
aXHelP! Displays the supported commands
Command Summary
measure Command