National Instruments NI PXI-5422 Verifying the Main Analog Path Offset

23. Subtract the Ideal Negative Full-Scale value from the Measured

Negative Full-Scale value and record the result under Error Negative

Full-Scale. The Error Negative Full-Scale value should be less than

or equal to the limit you are using.

24. Call niFgen_AbortGeneration (niFgen Abort Generation VI) to

abort the waveform generation using the following parameter:

•vi: The session handle returned from niFgen_init

25. Return to step 14 until iterations are completed.

26. Verify that both the Error Positive Full-Scale value and the Error

Negative Full-Scale value are less than or equal to the limit you are

using. If either of the errors is greater than the Calibration Test Limit

or the Published Specification, perform an external adjustment.

Verifying the Main Analog Path Offset

To verify the offset of the NI PXI-5422 main analog path, complete the

following steps:

1. Create an array of waveform samples for the mid-scale DC waveform

(0 VDC). This array should contain 500 samples with each sample

having the value 0.0 (representation: double).

2. 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 that you

created in step 1.

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

step 1.

•wfmHandle: The variable passed by reference through this

parameter receives the value (waveform handle) that identifies

the waveform created by this function (mid-scale handle).

3. Call niFgen_SetAttributeViInt32 to choose the mid-scale

handle DC 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 2 (mid-scale handle)

4. Repeat steps 5 through 15 for each of th e 24 iterations listed in Table 5,

changing the Ideal Positive Offset, Ideal Negative Offset, and Gain

values for each iteration. You can use Table 5 to record the results of

these steps.