I'm trying to simulate the properties of a modem using a virtual com port, so I need to control the ring indicator from labview application for simualting the modem properties.Kindly provide us idea for controlling the ring indicator signal from labview.
you can use a property node on the VISA Resource Name and select the property VISA Serial > Modem line > RI status. You also have all the other status lines available this way.
That property node is only for reading the status of the RI signal. If we try to assert the line using that property node you will get error.
In RS232 all signals are unidirectional with different directions in DCEs (modems) and DTEs (computers). RI is an output line in a modem and an input in a computer.
You will need to use one of the DTE output status lines, that is either RTS or DTR. I don't think there is a way to use RI as output from a computer.