Summary: Build a LabVIEW subVI to detect the first start bit in the Caller ID message bitstream.
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This module refers to LabVIEW, a software development environment that features a graphical programming language. Please see the LabVIEW QuickStart Guide module for tutorials and documentation that will help you: |
| • Apply LabVIEW to Audio Signal Processing | |
| • Get started with LabVIEW | |
| • Obtain a fully-functional evaluation edition of LabVIEW |
T
and F values), (2) steady mark
(constant T values), and (3) data block
containing the message payload.
This subVI detects the steady mark region and then identifies the array index
(time point) at which the input bitstream first changes to F.
bitstream in -- 1-D Boolean array Parentheses ( ) indicate default value; square brackets [ ] designate units.
datablock bitstream -- 1-D Boolean array start bit index -- I32 bitstream in input should contain a complete Caller ID message bitstream
as generated by other demodulating and bit synchronization and sampling subsystems.
datablock bitstream output contains only the data block portion of the
input bitstream, beginning with the first start bit of the first character, i.e., the first frame.
If no data block is detected then datablock bitstream will return empty.
start bit index is the index (location) of the data block detected
in the input message. If no data block is detected then start bit index will return -1.
View the screencast video in Create a SubVI in LabVIEW to learn the mechanics of subVIs.
Refer to the Figure 1 screencast video for LabVIEW coding tips and techniques specific to this subVI.
""Communication Systems Projects with LabVIEW" features ten projects that draw upon a library of over 40 subVIs constructed as part of the project activities. Each module in this manual completely […]"
"Starting point collection that gathers all modules from this course"