CR200/CR200X Series Dataloggers - Campbell Scientific
CR200/CR200X Series Dataloggers - Campbell Scientific
CR200/CR200X Series Dataloggers - Campbell Scientific
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Section 11. Programming Resource Library<br />
11.4.1.2.1 Start Measurement Command (aMv!)<br />
Qualifier v is a variable between 1 and 9. If supported by the sensor<br />
manufacturer, v requests variant data. Variants may include:<br />
• alternate units (e.g. °C or °F)<br />
• additional values (e.g., level and temperature)<br />
• diagnostic of the sensor’s internal battery<br />
Example:<br />
Command: 5M!<br />
Response: 500410 (atttnn, indicates address 5, data ready in 4 seconds, will<br />
report 10 values).<br />
Example:<br />
Command: 5M7!<br />
Response: 500201 (atttnn indicates address 5, data ready in 2 seconds, will<br />
report 1 value). v = 7 instructs the sensor to return the voltage of its internal<br />
battery.<br />
11.4.1.2.2 Start Concurrent Measurement Command (aC!)<br />
Concurrent measurement allows the <strong>CR200</strong>(X) to request a measurement,<br />
continue program execution, and pick up the requested data on the next pass<br />
through the program. The datalogger scan rate should be set such that the<br />
resulting skew between time of measurement and time of data collection does<br />
not compromise data integrity.<br />
Note This command is new to Version 1.2 or higher of the SDI-12<br />
Specification. Older sensors, older loggers, or new sensors that do not meet<br />
v1.2 specifications will likely not support this command<br />
11.4.1.2.3 Aborting a Measurement Command<br />
A measurement command (M! or C!) is aborted when any other valid command<br />
is sent to the sensor.<br />
11.4.1.3 Send Data Commands (aDv! & aRv!)<br />
11.4.1.3.1 Send Data Command (aDv!)<br />
This command requests data from the sensor. It is normally issued<br />
automatically by the datalogger after measurement commands aMv! or aCv!. In<br />
transparent mode, the user asserts this command to obtain data. If the expected<br />
number of data values are not returned in response to a aD0! command, the data<br />
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