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Keysight InfiniiVision M9241/42/43A PXIe Oscilloscopes SCPI Programmer's Guide
38
Synchronizing Acquisitions
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# How it works:
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The :DIGitize command is a blocking command, and thus, all
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other SCPI commands are blocked until :DIGitize is completely
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done.
This includes any subsequent processing that is already
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set up, such as math and measurements.
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KEY POINT: However, :DIGitize does not prevent additional
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commands from being sent to the queue or cause the remote
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program to wait.
For example, if your program does something
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like:
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KsInfiniiVisionX.write(":DIGitize")
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print("Signal acquired.\n")
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The "Signal acquired" message will be written immediately
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after the :DIGitize is sent, not after the acquisition and
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processing is complete.
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To pause the program until the :DIGitize is complete, you must
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wait for a query result after the :DIGitize.
For example, in
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this case:
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query_result = KsInfiniiVisionX.query(":DIGitize;*OPC?")
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print("Signal acquired.\n")
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The "Signal acquired" message will be written after the
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acquisition and processing is complete.
The *OPC? query is
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appended to :DIGitize with a semi-colon (;), which
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essentially ties it to the same thread in the parser. It is
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immediately dealt with once :DIGitize finishes and gives a "1"
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back to the program (whether the program uses it or not),
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allowing the program to move on.
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# Other Notes:
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If you DO NOT know when a trigger will occur, you should set a
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very long timeout.
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The timeout should be adjusted before and after the :DIGitize
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operation, though this is not absolutely required.
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A :DIGitize can be aborted with a device clear, which also
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stops the oscilloscope:
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KsInfiniiVisionX.clear()
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:DIGItize disables the anti-aliasing feature (sample rate
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dither) on all InfiniiVision and InfiniiVision X-Series
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oscilloscopes.
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:DIGitize temporarily blocks the front panel, and all front
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panel presses are queued until :DIGitize is done.
So if you
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change the vertical scale, it will not happen until the
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acquisition is done.
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The exception is that the Run/Stop button on the front panel