The Audio Test sequence demonstrates frequency domain measurements of audio tones
captured from the audio amplifier path.
This TestStand sequence uses the LabVIEW measurement libraries. By default, the test
sequence is installed to the following location: C:\Users\Public\Documents\National Instruments\PCB Assembly Test
Toolkit for LabVIEW\TestStand\Automation\Audio Tests
Required Driver Application Software
This
sequence requires a supported version of NI-DAQmx.
Highlighted Features
Audio Line Check—Sends a single-tone sine wave with an analog output and captures the sine wave with an
analog input. The example frequency domain measurements to validate the
audio amplifier path. Hardware triggers reduce the delay between signal
generation and signal capture. This example uses the following libraries:
DAQ_DC Signal Voltage Generation
DAQ_Frequency Domain Measurement
Audio Filter Check—Sends a multi-tone sine wave with an analog ouput and captures the sine wave with an analog
input. The example extracts the detected tones to verify the filter setup of
the DUT. Hardware triggers reduce the delay between signal generation and
signal capture. This example uses the following libraries:
DAQ_DC Signal Voltage Generation
DAQ_Frequency Domain Measurement
Turn Off all AO Channels—Powers down all analog output channels by configuring an output voltage of 0 V. This
example uses the DAQ_DC Voltage Generation library.
Hardware Configuration
The following figure illustrates the hardware connections for this example sequence.
Refer to the documentation for your specific device for pinouts and other
information necessary to adapt this example sequence to your application.
Using the Sequence with Physical Hardware
Run the sequence once in simulation mode. Running the sequence
in simulation mode creates the required global virtual channels in NI MAX that
you must modify.
Note In this
example, physical and global virtual channels are used to configure the
terminal or pin to perform the instrument actions. Global virtual channels
are software entities that encapsulate the physical channel along with other
channel specific information such as range, terminal configuration, and
custom scaling. You can create global channels in NI MAX and call them from
measurement libraries.
Right click the Import Hardware Config step and select Run Mode » Skip to skip the step.
Configure the remaining sequences. Open each sequence and
examine the Note to run with Hardware entry.
Configure the Audio Line Check sequence.
Open NI-MAX and update the physical channel linked to the global virtual
channels used in the Signal Voltage Generation and Frequency Domain
Measurement initialize steps: TS_AudioLineIn0 and
TP_AudioLineOut0. Refer to Creating and
Modifying Global Virtual Channels for more information.
Open the Frequency Domain Measurement – Configure
TP step and update the Digital Trigger
Source.
Review the analog output and analog input pin configurations for your
use case.
Save the sequence.
Configure the Audio Filter Check sequence.
Open NI-MAX and update the physical channel linked to the global virtual
channels used in the Signal Voltage Generation and Frequency Domain
Measurement initialize steps: TS_AudioLineIn0 and
TP_AudioLineOut0. Refer to Creating and
Modifying Global Virtual Channels for more information.
Open the Frequency Domain Measurement – Configure
TP step and update the Digital Trigger
Source.
Review the analog output and analog input pin configurations for your
use case.
Save the sequence.
Configure the Turn Off all AO Channels
sequence.
Open the DC Voltage Generation - Initialize AO
Channels step and update the Physical
Channels input to use your analog output channel.
Review the analog output pin configurations for your use case.
A virtual channel is a collection of settings such as a name, a physical channel, input terminal connections, the type of measurement or generation, and scaling information. A virtual channel that is created outside a task is a global virtual channel.