Introducing Message-Based DAQ

SCALE 1
Message Device response Description
"AI:SCALE=value" "AI:SCALE" Enables or disables scaling of A/D channels.
value = ENABLE or DISABLE
Example: "AI:SCALE=ENABLE"
"?AI:SCALE" "AI:SCALE=value" Returns a value indicating whether scaling will
be applied to the A/D channels.
value = ENABLE or DISABLE
1 These messages are processed by the DAQFlex Software library, and are not sent to the device.
Working with the CAL and SCALE properties
The ENABLE/DISABLE setting of the CAL and SCALE properties affect the kind of data that is returned:
• CAL=DISABLE, SCALE=DISABLE
If CAL and SCALE are both disabled, the data returned will be raw A/D integer values within the range of 0 to 2 res olution -1 of
the device. If the calibration factors are stored on the device and applied to the data by the application software, the data
range may be limited to well within these values.
• CAL=ENABLE, SCALE=DISABLE
When CAL is enabled and SCALE is disabled, the format of the analog data returned will depend on the type of calibration
implemented. If the calibration factors are stored on the device and applied to the data by the application software, the data
will be floating point values, not integer values, and may exceed the theoretical limits and include negative values and values
above 2 res olution -1.
• SCALE=ENABLE
When SCALE is enabled, scaled floating point values are returned. The limits of the data will depend on the implementation of
calibration, as described above. Data range limits may be a small percentage less than or greater than the full scale range
selected for devices for which the calibration factors are stored on the device and applied to the data by the application
software.
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