Teledyne HDO9000, Руководство оператора

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HDO9000 High Definition Oscilloscopes Operator's Manual
Fast Wave Port Function
Fast Wave Port is a function of Teledyne LeCroy X-Stream oscilloscopes that enables you to insert
your own custom algorithm, written in the C/C++ language, into the oscilloscope's processing stream.
It also maximizes data throughput from the acquisition system to your custom algorithm for purposes
of debugging. Custom algorithms can be written right on the oscilloscope using the Web Editor.
This is possible because two Windows system processes may share a region of memory, enabling
high-speed data transfer between the acquisition system and the custom algorithm, which runs in a
separate process from the oscilloscope application. A major benefit of Fast Wave Port is that your
algorithm may be implemented and, more importantly, debugged independently of the main
application.
It is important to note that transferring the results of your algorithm back into the X-Stream
processing stream is optional. If performance is the primary goal, and further processing of the
results within the X-Stream software is not required, this step may be skipped.
Fast Wave Port was designed for use with the C/C++ programming language. However, it is
theoretically possible for the processing to be implemented in any language supporting Windows
named events (Mutex) that can open a named memory-mapped file. No guarantee can be given,
however, as to the behavior of the function using anything but C/C++.
The size of the memory window is fixed at 80 MB, equating to 40 ms.
To use Fast Wave Port, follow the usual steps to set up a math function , selecting Fast Wave Port as
the Operator, then make the appropriate settings on the Fast Wave Port subdialog.
The Port Name is critical, indicating the base name of the memory window and the global objects
within the Windows O/S. Only change the default value if using multiple Fast Wave Port functions in
parallel.
Note: The base name must match the base name used in the client application.
The full names of the default global objects are as follows:
Object Full Name
Memory Mapped File FastWavePort1File
Data Available Event FastWavePort1MutexDataAvailable
Processing Complete Event FastWavePort1MutexProcessingComplete
The Timeout control specifies the amount of time the DSO waits for the custom processing function
to complete. This prevents the DSO from waiting indefinitely for a custom processing function which
may never arrive. Be careful to set this control to a reasonable value, meaning a time longer by a
reasonable margin than the custom processing is ever expected to take.
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