How to send a scpi command to a device in some slot of a PXI chassis?

I have been able to send a scpi command to an oscilloscope using SCPI instrument and SCPI test step.
Now I need to send a scpi command to a device in some slot of a PXI chassis, what should I do?
Just modify the VISA address of Genneric SCPI Instrument to actual PXI address like PXI0::23-0.0::INSTR?
Do I need to install some drive for PXI support?
Thanks for any help!

Hi @allen ,

You can create a custom instrument plugin based on the ScpiInstrument class. You need to use the drivers of the instrument though.

I developed an instrument plugin for the PXIe-2575 instrument before. For the PXIe-2575, I used NISwitch .NET API in the instrument plugin to see the available PXI devices and communicate with it.

image

This is one way of doing it and it requires development using annotations, but maybe there are other ways. If you want to develop a custom instrument plugin as I did, you can see the IPAnnotation example in the SDK examples.

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PXI instruments are interesting. A few of them from Keysight have a SCPI server, but many just have an IVI driver for control, which you could use to build an Instrument plugin for, like @btyilmaz suggests.

Is there a specific PXI model you are interested in?

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Maybe I will need to connect PXI models of NI, Keysight or some other manufacturer. If I have to connect PXI devices from different manufacturer, Do I need to install all of the different IVI or PXI drivers provided by their manufacturers? It seems not a good idea.

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Joining in the discussion.
We have created a Generic IVI Instrument, So were able to connect to any IVI instrument and call the exact methods. VISA instruments share common features, so we are able to connect to any VISA instruments.

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Hi,justin,
which software and version include this IVI Instrument?
I didn’t see IVI Instrument in Developer’s System CE 9.17.4
https://packages.opentap.io/index.html#name=%2FPackages%2FDeveloper’s+System+CE&version=9.17.4%2B5e508f08&os=Windows&architecture=AnyCPU

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Sorry Allen, This is not an in-built Open Tap feature.
This is a separate plugin created by another team,
I just want to let you know about what we have done.

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Yes you would need specific software for each PXI device @allen . The reason is that PXI cards are basically PCI/PCIe devices, so they really just expose a register map / DMA type interface. Most vendors don’t expose that level of detail to the user because these are fairly complex devices and that would not be a good user experience. Instead, they’ll implement firmware/software that runs on the PC, which implements the control logic and some measurement algorithms. Then we’ll expose that firmware through a .dll, and usually an IVI driver on top, to expose that to the end customer. On a “big box” instrument, all the firmware/software ends up inside of the box, and you control it remotely over SCPI. For some instruments at Keysight we add a SCPI layer over top of the PXI firmware / .dll, but thats not always the case. You’ll usually see it in our PXI products that share common firmware with one of their box instrument siblings, like our PXI VNA’s. More unique PXI cards won’t have a SCPI interface.

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