Chapter 3
Adjustment
©
National Instruments Corporation
3-7
Determining the Output Dependence On the Gain of the
Gain Calibration DAC (Constant A2)
To determine the output dependence, measure output while sweeping the full
scale of values for the gain calibration DAC, with the offset calibration DAC
and the main DAC set to 0. Measure the outputs for each setting of the gain
DAC.
1.
Set the offset calibration DAC to zero by calling the function
ni54xx_SetOffsetDAC
. Set the following parameters:
•
sessionHandle
—The handle of the calibration session for the
device
•
DACValue
—
0
2.
Generate a 0 V DC waveform by calling the function
ni54xx_GenerateWaveform
. Set the following parameters:
•
sessionHandle
—The handle of the calibration session for the
device
•
waveType
—
NI54XX_DC
•
amplitudeInVolts
—
0
•
frequencyInHz
—
0
3.
For each of the following values for
x
, where
x
= (–8192, –6144, –4096,
–2048, 0, 2048, 4096, 6144, 8191), complete the following steps:
a.
Set the gain calibration DAC to
x
by calling the function
ni54xx
_SetGainDAC. Set the following parameters:
•
sessionHandle
—The handle of the calibration session for the
device
•
DACValue
—
x
b.
Measure the outputs (
measurements[]
).
4.
Call
ni54xx_CalAdjust
using the output measurements from step 3b
as the
measuredData
and the array of DAC settings as the
actualData
of DAC settings using the following parameters:
•
sessionHandle
—The handle of the calibration session for the
device
•
measurementMode
—
NI54XX_SET_A2
•
actualData
—
offsetSweepDACValues
•
measuredData
—
measurements
You have completed measuring the outputs for the constant A2.