Chapter 3
Adjustment
3-10
ni.com
7.
Feed the measurements to
ni54xx_CalAdjust
. The
measuredData
are the new array of measurements, and the
actualData
are the DAC
values corresponding to outputs (see Table 3-2). Call the function
ni54xx_CalAdjust
using the following parameters:
•
sessionHandle
—The handle of the calibration session for the
device
•
measurementMode
—
NI54XX_SET_A4
•
actualData
—
mainDACSweepValues
•
measuredData
—
mainDACSweepResults
Determining the Low Frequency Gain of the Analog Filter
(Constant A7)
Generate a low frequency sine wave output with the analog filter disabled and
measure the outputs. Repeat the process with the analog filter enabled, and
pass both measurement results to
ni54xx_CalAdjust
. You can measure
the amplitude, peak-to-peak amplitude, or RMS value, as long as both
measurements are the same.
1.
Set the offset calibration DAC to 0 by calling the function
ni54xx_SetOffsetDAC
. Set the following parameters:
•
sessionHandle
—The handle of the calibration session for the
device
•
DACValue
—
0
2.
Set the gain calibration DAC to –4079 (the approximate value for a gain
of 1) by calling the function
ni54xx_SetGainDAC
. Set the following
parameters:
•
sessionHandle
—The handle of the calibration session for the
device
•
DACValue
— –
4079
3.
Generate a full scale sine wave at 500 Hz by calling the function
ni54xx_GenerateWaveform
. Set the following parameters:
•
sessionHandle
—The handle of the calibration session for the
device
•
waveType
—
NI54XX_SINE
•
amplitudeInVolts
—
10
•
frequencyInHz
—
500
4.
Measure the outputs (
lowFrequencyAmplitude
).