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Flow control control for serial VISA???

Hello,
in the "old" serial VIs (Configure serial port, LV 6 and older), there was a cluster of different flow control options, including Input XON/XOFF, Input HW Handshake, input alt HW hdshk, output XON/XOFF, output XON/XOFF, output HW hdshk, XON byte, XOFF byte, Parity error byte. The VISA Configure Serial Port VI only supports a control offering the options NONE, XON/XOFF, RTS/CTS, DTR/DSR and "other". How am I supposed to convert the old values of my old handshake cluster to this new control? I cannot change the input (which is exactly that old cluster that I mentioned before), so I need to convert the given values into the correct selection for the new control. Please help.

General question : When changing all communicatio
n VIs from the old ones to VISA, is there anything special that I must take care of? Are there any sample VIs showing how to replace the old original serial and GPIB VIs with the corresponding VISA functions, but using the same input controls as before (to keep the user interface compatible)?

Thanks in advance for your fast help,
Gabs
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Message 1 of 10
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Open Configure serial port and extend the propertynode inside.select the new created property and look what properties are available.
I'm sure that you find most of the settings formerly available in the flow control cluster.
Be sure to save the new Open Serial port under a new name in your own folders.
succes
greetings from the Netherlands
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Message 2 of 10
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Hello,
thanks for your reply. I tried to do this, but the only additional properties that I find there are the XON and XOFF characters. I have no idea how I can wire the rest of the "old" input controls that I mentioned (from LabVIEWs former native serial VIs) to the inputs of the corresponding VISA function. I would have expected that the native Configure serial port VI and the VISA Configure serial port VIs would have the same input connectors, but that is not true, unfortunately! Isn't there any sample VI available that shows how to do that? Compatibility is a big point for us when switching to VISA functions.
Regards,
Gabs
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Message 3 of 10
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What are the values that you need to change?
greetings from the Netherlands
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Hi,
please find attached the two VIs that I am talking about. You'll see that both VIs are supposed to do the same thing, acutally it was my understanding that the VISA Configure Serial Port.vi is supposed to replace the Serial Port Init.vi. Unfortunately, the input controls that I needed for the former one are not compatible with the second one. I was able to solve that problem for all input controls except the flow control input.
Gabs
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Message 5 of 10
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These are the generic versions, I have them too.
What I tried to ask was your way of calling this old vi.
I mean what are the settings within flowcontrol that you are trying to set. This is only done at the beginning of your project, so it should be easy to find.
greetings from the Netherlands
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Message 6 of 10
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I have a "Flow control" cluster wired to the "Flow Control" input of the old generic VI, which looks exactly as the one on the panel of the old VI. The user had the chance to put all available flow control information into this cluster and the whole cluster was sent to the serial VI without modification (the reason why I was doing this is that the main VI is kind of a terminal application that is able to talk to many different devices using different serial settings). I must keep the input cluster of my main VI but must find a way to wire the information from this cluster to the new VISA Flow Control connector. Is this what you were asking for?
Regards,
Gabs
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Message 7 of 10
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Hi Gabi

I guess that you have two options.
First the best: Change your user interface.
The old serial flow control has a nasty user interface.
It is not very good for a normal user because you can select items that exclude each other.
Like input Xon and hardware handshake.
Second: you can deliver the old serial libraries and serpdrv. This should still work. And keep the old interface.
greetings from the Netherlands
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Message 8 of 10
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Gabs:

Assuming you have LV 7, you may wish to look at the compatibility VI that we ship with LV. It's in vi.lib/Instr/serial.llb and it's called Serial Port Init.vi. It converts from using the old-style cluster to calling the VISA functions. As everyone has pointed out, it's ugly. But it does work.

Note that the old-style VI did in theory support one-directional handshaking, for example, hardware handshaking out but not handshaking in. For any given type of handshaking, VISA supports it bidirectionally, so the VI just does an 'or' of the 2 values. But I can only recall 1 user who ever had a need for that, so it most likely won't be an issue for you. In general, VISA has the superset of Serial functionality.

Dan Mondrik
National Instruments
Message 9 of 10
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Hello Albert and Dan,
sorry that I have not answered on your replies again. During the message board rework, I got no notifications anymore. Someone from NI helped me with the cluster conversion, so I was able to solve my problem in time. A belated thank you for your replies, which would have been helpful, too!!
Greetings,
Gabs
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