National Instruments SCXI-1141, Calibration Procedure

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© National Instruments Corporation 17 SCXI-1141/1142/1143 Calibration Procedure
10. Call the
SCXI_SetDP
function in
SCXIdpCal.dll
to set the digital
potentiometer to a neutral position, set the following short integer
parameters:
• SCXIchassisID —The value obtained from MAX
• moduleSlot —4
• channel —0
• value —127
11. Measure the amplitude of the sine wave at the output of the module.
12. If the measured value is less than the value measured with the filter
bypassed, increase the value to which the digital potentiometer is set.
If it is greater, decrease the value. You can set the digital potentiometer
from 0 to 255.
13. Call
SCXI_SetDP
to set the digital potentiometer to the new value:
• SCXIchassisID —The value obtained from MAX
• moduleSlot —4
• channel —0
• value —The new value decided upon in step 12
14. Repeat steps 11 through 13 until the measured amplitude is as close as
possible to the level it was with the filter in bypass mode.
15. Repeat steps 4 through 14 for the remaining channels.
You have finished adjusting the filter AC gain of the
SCXI-1141/1142/1143.
Verifying Adjusted Values
After you complete the adjustment procedure, it is important that you verify
the accuracy of the adjusted values by repeating the procedure in the
Verifying the Operation of the SCXI-1141/1142/1143 section. Verifying
the adjusted values ensures that the SCXI-1141/1142/1143 is operating
within its specifications after adjustments.
Note If the module fails verification after adjustment, return it to NI for repair or
replacement.
Front and Rear Panel Pin Assignments
Table 7 shows the pin assignments for the SCXI-1141/1142/1143 front
panel connector.