Pulse Feedback

I wonder if someone can help me out here.

Here is the situation.
We want to control the rotation of a roll. We have a proximity switch as a velocity feedback signal. Currently this roll is controlled by a controller dedicated for this purpose. This is a slow reaction system, we don’t need more. We want to centralize all axes to make the system simpler to manage. We are using RMC150E for other axes on the system.

The question.
What will you do to control this roll in closed-loop with a RMC150E ?

What comes to my mind.
First, I thought to use a Quad module. But then, I thought I cannot use only the phase A. I need a phase A and B to have increasing and decreasing counts. Am I right ?

Secondly, I thought to use one of the discrete input on CPU module. Using the Prescan table and a program I can easily increase a value or calculate a speed. But I don’t know how to put this feedback into the velocity closed-loop.

Any simple ideas are welcome !

Converting to an analog signal or to a quadrature A,B signal is the best method.
We have some suggestions in this topic: Pulse Train signal converters

Thank you infinitely!