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Auto Setup a four channel oscilloscope using two NI 5112 boards

I have two NI 5112 boards and want to design a four channel oscilloscope supporting auto setup.

I refer to the "niScope EX Getting Started.vi". I have studied the "niScope Initialize" and "niScope Auto Setup" in the "NI SCOPE VI Reference Help".

The "niScope Auto Setup" generates no trigger output. Would it still be possible to auto setup a four channel synchronized display using two NI 5112 boards?

How can I using property nodes or by other means find out:
1. If there is a signal present on ch0 and what vertical range "niScope Auto Setup" has setup?
2. If there is a signal present on ch1 and what vertical range "niScope Auto Setup" has setup?
3. If there is no signal on a certain channel?

I
intend to use and modify the �niScope EX 5112 Synchronization.vi�
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There are no NI-SCOPE functions to automatically do an autosetup on two synchronized 5112s. However, you can use niScope Auto Setup.vi on each of the 5112s individually, then reset the slave trigger parameters back to digital with the proper source. The other synch parameters (clock out/in, synch pulse, trigger out) should not be effected by the auto setup.

If the autosetup routine cannot find a signal on either channel, it will return a warning. If autosetup cannot detect a signal on a particular channel, it will set the lowest possible vertical range. To find out if there is a signal on a particular channel, take a short data set and look at it. NI-SCOPE does not provide a way to get this information any other way. If you know your signals wi
ll always produce a range greater than the smallest range of the 5112, you can use the vertical range as the way of telling that no signal was detected.

You can query almost any current parameter from the driver using property nodes. The vertical range is channel specific, so first set the Active Channel, then query for Vertical->Vertical Range. A word of warning when querying parameters. NI-SCOPE is IVI compliant, so the values you get from querying the property nodes are based on the IVI specification, not the NI-SCOPE LabVIEW API. Sources will always be strings and some properties have the same format, but different mappings. For example, the trigger slope in the LabVIEW API is mapped 0-positive, 1-negative. If queried from the property node, 0 is negative and 1 is positive due to the IVI spec. There are not many of these. You can easily find them by looking in the block diagram of the set VIs for look-up tables (array constants).

Good luck! If you
still need more help, post a reply


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