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National Instruments Corporation
17
NI 5421/5441 Calibration Procedure
10. Call
niFgen_CreateArbWaveform
(niFgen Create Arbitrary
Waveform VI) using the following parameters:
•
vi
: The session handle returned from
niFgen_init
•
wfmSize
: The size in samples (
500
) of the waveform you created
in step 9
•
wfmData
: The array of waveform samples that you created in
step 9
•
wfmHandle
: The variable passed by reference through this
parameter receives the value (waveform handle) that identifies
the waveform created by this function.
11. Call
niFgen_InitiateGeneration
(niFgen Initiate Generation VI)
to initiate the waveform generation using the following parameter:
•
vi
: The session handle returned from
niFgen_init
12. Measure the frequency out of the NI 5421/5441.
A frequency error of 45 Hz for a 10 MHz signal corresponds to an
error of 4.5 ppm. This limit accounts for the initial accuracy and the
frequency deviation caused by temperature and aging. Refer to Table 3
for frequency ranges.
13. Call
niFgen_AbortGeneration
(niFgen Abort Generation VI) to
abort the waveform generation using the following parameter:
•
vi
: The session handle returned from
niFgen_init
14. Call
niFgen_close
(niFgen Close VI) to close the instrument
driver session, to destroy the instrument driver session and all of
its properties, and to release any memory resources NI-FGEN uses.
Use the following parameter:
•
vi
: The session handle returned from
niFgen_init
Table 3.
Frequency Ranges
Calibration Test Limit
Published Specifications ±25 ppm
Low
High
Low
High
9,999,955 Hz
10,000,045 Hz
9,999,750 Hz
10,000,250 Hz
