Campbell Scientific CR200/CR200X-series Dataloggers - Manual (Page 130)

Section 11. Programming Resource Library
SDIRecorder () Instruction
SDICommand Entry Actions Internal to CR200(X) and
Sensor
Mv! CR200(X)
: Issues aMv! command
Sensor : Responds with atttnn
CR200(X)
: Waits until ttt 1 seconds.
Issues aDv! command(s)
Sensor
: Responds with data.
Cv! CR200(X)
: Issues aCv! command
Sensor
: Responds with atttnn
CR200(X) : If ttt=0 then issues aDv!
command(s)
Sensor : Responds with data.
CR200(X)
: else, if ttt>0 then moves to
next CRBASIC program instruction.
CR200(X) : At next time SDIRecorder()
is executed, if elapsed time < ttt, moves
to next CRBASIC instruction,.
CR200(X)
: else, issues aDv!
command(s)
Sensor : Responds with data.
CR200(X)
: Issues aCv! command (to
request data for next scan).
Cv (note: no ! termination)
CR200(X) : Tests to see if ttt expired.
If ttt not expired, loads "1e9" into first
variable then moves to next CRBASIC
instruction. If ttt expired, issues aDv!
command(s).
Sensor : Responds to aDv! command(s)
with data, if any. If no data, loads NAN
into variable.
CR200(X) : moves to next CRBASIC
instruction (does not re-issue aCv!
command).
1 Note that ttt is local only to the SDIRecorder() instruction.
11.4.3 SDI-12 Power Considerations
When a command is sent by the datalogger to an SDI-12 probe, all probes on
the same SDI-12 port will wake up. Only the probe addressed by the datalogger
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