I have not learned to SEARCH the forum.

How about I return to basics. How about I make my controls interrupt driven. If had an interrupt routine that ran every 20msec, I could create a true-so-spec PWM signal and I could measure rate of closing speed for each SONAR. I think the 16F887 can get all my work done in 20msec. If not I can up the PIC power.

Way back someone told me how to set up such an interrupt system. Where is that? It's Monday morning. Time to get moving.

Ken