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NI 5421/5441 Calibration Procedure
b.
Call
niFgen_CalAdjustOscillatorFrequency
(niFgen Cal Adjust Oscillator
Frequency VI) using the following parameters:
•
vi
: The session handle returned from
niFgen_InitExtCal
•
desiredFrequencyInHz
: The desired frequency (
10000000
) of the generated
sinusoid in Hz
•
measuredFrequencyInHz
: The
measured frequency
of the generated
sinusoid in Hz
c.
Call
niFgen_InitiateGeneration
(niFgen Initiate Generation VI) to initiate the
waveform generation using the following parameter:
•
vi
: The session handle returned from
niFgen_InitExtCal
d.
Measure the frequency of the generated waveform. This value is the
Measured
Frequency
.
16. Call
niFgen_AbortGeneration
(niFgen Abort Generation VI) to abort the waveform
generation using the following parameter:
•
vi
: The session handle returned from
niFgen_InitExtCal
Adjusting the Calibration ADC
The NI 5421/5441 has an onboard calibration ADC used during self-calibration. To adjust the
calibration ADC, characterize the gain and offset associated with this ADC so that a
self-calibration results in an accurately calibrated device.
1.
Call
niFgen_InitializeCalADCCalibration
(niFgen Initialize Cal ADC
Calibration VI) using the following parameter:
•
vi
: The session handle returned from
niFgen_InitExtCal
2.
Call
niFgen_WriteBinary16AnalogStaticValue
(niFgen Write Binary 16 Analog
Static Value VI) to set the main DAC value using the following parameters:
•
vi
: The session handle returned from
niFgen_InitExtCal
•
channelName
:
"0"
•
value
:
0
3.
Call
niFgen_SetAttributeViInt32
to set the analog path value (NI-FGEN Analog
Path property) using the following parameters:
•
vi
: The session handle returned from
niFgen_InitExtCal
•
channelName
:
"0"
•
attributeID
:
NIFGEN_ATTR_ANALOG_PATH
•
value
:
NIFGEN_VAL_FIXED_LOW_GAIN_ANALOG_PATH
4.
Call
niFgen_SetAttributeViInt32
to set the gain DAC value (NI-FGEN Gain DAC
Value property) using the following parameters:
•
vi
: The session handle returned from
niFgen_InitExtCal
•
channelName
:
"0"
•
attributeID
:
NIFGEN_ATTR_GAIN_DAC_VALUE
•
value
:
1700