CLAD Data Acquisition & Instrument Control 2

Question 1

Which NI-DAQmx function is used to read analog input samples into a LabVIEW waveform data type?

Accepted Answer

DAQmx Read (Analog Wfm 1Chan NSamp)

Answer

DAQmx Read (Analog Wfm 1Chan NSamp) returns a waveform that bundles the data array with timing (t0 and dt) for a single analog input channel.

Question 2

What is the purpose of the DAQmx Timing (Sample Clock) VI?

Accepted Answer

It configures how and when samples are acquired or generated

Answer

DAQmx Timing (Sample Clock) sets the source, rate, active edge, and sample mode (finite vs. continuous) for a DAQmx task.

Question 3

In NI-DAQmx, what does setting the sample mode to 'Continuous Samples' require compared to 'Finite Samples'?

Accepted Answer

A loop that calls DAQmx Read repeatedly to drain the buffer

Answer

Continuous acquisition fills a circular buffer indefinitely, so the application must call DAQmx Read in a loop to consume samples and prevent buffer overflow.

Question 4

Which VISA function opens a communication session with an instrument and returns a session reference?

Accepted Answer

VISA Open

Answer

VISA Open establishes a session with a specified resource name and returns a VISA session refnum used by all subsequent VISA calls.

Question 5

A strain gauge sensor outputs 0–10 mV. Which DAQ hardware feature should you enable to measure it accurately without amplifying the signal externally?

Accepted Answer

Instrumentation amplifier / programmable gain

Answer

An instrumentation amplifier with programmable gain amplifies the low-level millivolt signal to match the ADC's full input range, improving resolution and SNR.

CLAD Practice Test

CLAD Practice Test

CLAD Data Acquisition & Instrument Control 2