700-SDI-RADAR-300W-Man Rev 2 30 May 2022
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Part# 21370
A.3
TROUBLESHOOTING SDI-12 ADAPTER ERRORS
In the event that communication is lost between the SDI-12 Adapter and the radar,
the SDI-12
datalogger will still be able to communicate with the SDI-12 adapter, but the adapter will not be
able to retrieve the data from the radar. This section describes the behavior of the SDI-12
adapter when communication with the radar is lost.
A.3.1
Verification command errors
On initial adapter power-up, the adapter will try to communicate with the radar. If the radar is
reachable from the adapter, the adapter will internally store the radar status to
OK;
otherwise the
internal radar status will be stored as
ERROR
. This status is not reported, unless the user issues a
verify command (aV!).
The second result returned by aD0! Issued after aV! Command will return the last known radar
status.
The following command sequence can be used to verify the last known radar status:
1. If the radar status is OK:
Command : 1V!
Response : 10002<CR><LF>
Command : 1D0!
Response : 1+1+1<CR><LF> (1 = radar error)
2. If the radar status is in ERROR:
Command : 1V!
Response : 10002<CR><LF>
Command : 1D0!
Response : 1+1+0<CR><LF> (0 = radar error)
Note that the SDI-12 adapter checks the radar status on the initial power-up. If the radar is not
connected during the adapter power-up, and then subsequently connected, issuing the Verify
command will return the last known radar status, which is ERROR, even though the radar instrument
is actually connected and operational. In this case, in order to get the correct status, a
measurement command (aM!) followed by a Verify command (aV!) must be issued.
