@inq Thanks. I will try your suggestion. I will repost the Arduino (ino) file as well and get back to you.

@will Hi Will, Well, I finally narrowed it down. I swapped out the Arduino UNO board with one I had purchased in September. After I got...

@will Thanks Will, The wiring looks exactly the same! I'll read the article.

@will Thanks Will, That 5 you see on the diagram is " + 5V", I have the OPTO lead connected to a 5 volt terminal on the Arduino. The atta...

Hi Will I have attached the circuit diagram from OMC Support. I'm going to try checking the control lines with a scope to check for a signal. I ...

@will Thanks, I have tried that without success. It makes sense to connect ENA but the OMC user manual, page 10, says that ENA is left NC (not con...