Can I monitor the status of the serial flow control

[oldmanXJ]

I have a complex byte error tester written in LV.  It works great but in one mode of testing a unit, the throughput falls off severely.  Is there a way to see if the UUT is exerting a flow control in real time?  Yes, I have flow control enabled, I just would like to be able to see if that is what is slowing down the transfers.

[RTSLVU]

Right off the top of my head I would say use one of the old serial breakout boxes with the LED's on the flow control lines. 

There are a few serial sniffer programs out there, but they tend to focus on sniffing the data and ignore the flow control. 

[oldmanXJ]

Thanks for the input.  Being an old guy, I know about the breakout boxes, but I was hoping there was a system level call that would give you visibility in the program.

I played with the NI I/O sniffer program but I didn't see where I could monitor the control lines.

[crossrulz · Accepted solution]

Using a VISA Property Node, you can get the state of a bunch of modem signals (Serial Settings->Modedem Line Settings).  The CTS and DSR lines are the ones you would likely want to watch.

[RavensFan]

You can check the status of the hardware flow control lines using a property node.

[oldmanXJ]

Thanks.  That is what I was looking for

[RavensFan]

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