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National Instruments VXI-MIO Series User Manual

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Appendix C Common Questions

National Instruments Corporation

C-3

VXI-MIO Series User Manual

while maintaining a high common-mode rejection ratio (CMRR).
These methods are outlined in Chapter 4,

Signal Connections

.

9.

Can I sample across a number of channels on a VXI-MIO Series

module while each channel is being sampled at a different rate?

NI-DAQ features a function called

SCAN_Sequence_Setup

,

which allows for multirate scanning of your analog input channels.
Refer to the

NI-DAQ Function Reference Manual for PC

Compatibles

for more details.

10. I’m using the DACs to generate a waveform, but I discovered with

a digital oscilloscope that there are glitches on the output signal. Is
this normal?

When it switches from one voltage to another, any DAC produces
glitches due to released charges. The largest glitches occur when
the most significant bit (MSB) of the D/A code switches. You can
build a lowpass deglitching filter to remove some of these glitches,
depending on the frequency and nature of your output signal. The
VXI-MIO-64E-1 module has built-in reglitchers, which can be
enabled through software, on its analog output channels. See the

Analog Output Reglitch Selection

section in Chapter 3 for more

information about reglitching.

11. Can I synchronize a one-channel analog input data acquisition

with a one-channel analog output waveform generation on my
VXI-MIO Series module?

Yes. One way to accomplish this is to use the waveform generation
timing pulses to control the analog input data acquisition. To do
this, follow steps a through d below, in addition to the usual steps
for data acquisition and waveform generation configuration.