Audio with a PLC?

I have a Beckhoff CX1020 demo system running Windows CE at my school. There are multiple stepper motors connected to the system that spin in a sequence that was programmed by someone else.

My question is, can I use an analog audio input to control a single stepper motor at a desired sound frequency? Is there an analog card I can use to acquire a sound frequency?

Please let me know if you need additional info. I still learning about the PLC world.

-Jesse

Jmickle said:

My question is, can I use an analog audio input to control a single stepper motor at a desired sound frequency? -Jesse

Click to expand...

I doubt an audio stream would do it (realtime) without significant horsepower and memory.
But look here
here

Maybe. There is an EtherCat analog input (EL3702) that is supposed to be good up to 30kHz. The question is will you be able to do the signal processing to pull out the frequencies in what amounts to a plc. I don't know if the CX1020 has the tools available to do that.

Keith

You will need FFT, for this, and thats a little too much asked for a PLC system.
However it is possible with a simple filter and a transistor.
with the filter (a cap and a resistor ) you make a sound filter, so one freq will be highlighted and the rest will be lower.
then a diode to a transistor will open when the frequency is present at the input. This can go to an input of the plc, and that can make a stepperfrequency.