Chapter 3
Adjustment
3-18
ni.com
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 5 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
—
5
•
frequencyInHz
—
0
4.
Set the calibration multiplexer to route the device output and the
internal reference to the calibration ADC by calling the function
ni54xx
_SetCalibrationMux. Set the following parameters:
•
sessionHandle
—The handle of the calibration session for the
device
•
muxSetting
—
NI54XX_OUT_VS_REF
5.
Read the value of the calibration ADC by calling the function
ni54xx_ReadCalibrationADC
. Set the following parameters:
•
sessionHandle
—The handle of the calibration session for the
device
•
calADCValue
—
¤tCalADCValue
6.
Measure the outputs (
currentOuput
).
7.
Call
ni54xx_CalAdjust
for the internal reference. The
measuredData
should be a pointer to the calibration ADC reading. The
actualData
should be a pointer to the value of the device output. Call
the function
ni54xx_CalAdjust
using the following parameters:
•
sessionHandle
—The handle of the calibration session for the
device
•
measurementMode
—
NI54XX_SET_INTERNAL_REFERENCE