2 check unit response, 3 check for valid data, Check unit response – Campbell Scientific CS475, CS476, and CS477 Radar Water Level Sensor User Manual
Page 30: Check for valid data, 1. example of start measurement command, 2. acknowledge, Active, Command, Section 8.1.3, See table 8-1)

CS475, CS476, and CS477 Radar Water Level Sensor
• Stage—the water level as measured in meters or feet. This measurement is
calculated using the Water Stage Setting and the Units setting.
• Distance—the distance between the sensor and water surface. This value
will be reported in either meters or feet, depending on the Units setting.
• Diagnostic Values—an error code. For example, Code 0 = OK, Code 13 =
error E013 (see Section 8.2, Diagnostics and Repair).
TABLE 8-1. Example of Start Measurement Command
Initial Command
Response
0M! 
Where zero is the 
sensor address. 
00023
0—sensor’s address; 
002—the amount of time (in seconds) that you must 
wait before sending the send data command; 
3—the number of values that will be placed in the 
buffer. 
Subsequent 
Command 
Response
0D0! 
Where the first zero is 
the sensor address. 
0+100.050+25.000+0
0—sensor’s address; 
100.050—the stage in meters or feet; 
25.000—the distance in meters or feet; 
0—error code. 
8.1.2 Check Unit Response
The Acknowledge Active command is used to check the presence of the sensor 
on the bus (see TABLE 8-2). 
TABLE 8-2. Acknowledge Active Command
Initial Command
Response
a!
a
8.1.3 Check for Valid Data
The aI! command gets the following identification information in response to 
sending aI! (see TABLE 8-3). 
• Compatibility level: Version of SDI-12 protocol version; for example, 1.3.
• Manufacturer’s Name: VEGA
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