National Instruments NI PXI-5422

NI PXI-5422 Calibration Procedure 54 ni.com

9. Call niFgen_CreateArbWaveform (niFgen Create Arbitrary

Waveform VI) using the following parameters:

•vi: The session handle returned from niFgen_InitExtCal

•wfmSize: The size in samples (500) of the waveform you created

in step 8

•wfmData: The array of waveform samples that you created in

step 8

•wfmHandle: The variable passed by reference through this

parameter receives the value (waveform handle) that identifies

the waveform created by this function.

10. Call niFgen_SetAttributeViInt32 to choose the sine waveform

(niFgen property node: Arbitrary Waveform Output»Arbitrary

Waveform Handle) using the following parameters:

•vi: The session handle returned from niFgen_init

•channelName: "0"

•attributeID: NIFGEN_ATTR_ARB_WAVEFORM_HANDLE

•value: The wfmHandle from step 9 (sine waveform handle)

11. Call niFgen_InitiateGeneration (niFgen Initiate Generation VI)

to initiate the waveform generation using the following parameter:

•vi: The session handle returned from niFgen_InitExtCal

12. Measure the frequency of the generated waveform. This value is the

measured frequency, which is used in step 13.

13. Repeat steps 13a through 13d for as long as the difference between the

measured frequency and the desired frequency (10 MHz) is greater

than the tolerance (4.5 ppm).

The measured frequency should converge on the desired frequency.

If the measured frequency does not converge on the desired frequency

within 16 iterations, a problem may exist with your measurement

device or the NI PXI-5422.

a. Call niFgen_AbortGeneration (niFgen Abort Generation VI)

to abort the waveform generation using the following parameter:

•vi: The session handle returned from niFgen_InitExtCal

b. Cal l 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