National Instruments PCI-6110E/6111E - Manual (Page 85)

Appendix C Common Questions
PCI-6110E/6111E User Manual C-2 © National Instruments Corporation
What type of 5 V protection does the 611X E board have?
The 611X E board has 5 V lines equipped with a self-resetting 1 A fuse.
Installation and Configuration
How do you set the base address for the 611X E board?
The base address of the 611X E board is assigned automatically through
the PCI bus protocol. This assignment is completely transparent to you.
What jumpers should I be aware of when configuring my
611X E board?
The 611X E board is jumperless and switchless.
Which National Instruments document should I read first to get
started using DAQ software?
Your NI-DAQ or application software release notes documentation is
always the best starting place.
Analog Input and Output
I have connected a differential input signal, but my readings are
random and drift rapidly. What’s wrong?
Check your ground reference connections. Your signal may be
referenced to a level that is considered floating with reference to the
board ground reference. Even if you are in differential mode, the signal
must still be referenced to the same ground level as the board reference.
There are various methods of achieving this while maintaining a high
common-mode rejection ratio (CMRR). These methods are outlined in
Chapter 4, Signal Connections.
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.
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