I can see how it could all be done with a single mcu but the code is free
and I have some extra 873s in the junk box so I am not going to reinvent it.
I do like the idea of putting out a NMEA statement though. Wonder if there
is a standard prefix for rode length?

He used a Hall effect sensor but I have several Omron industrial strength
proximity sensors left over from the engine driven watermaker project. I
used one to detect the bolt heads on the PTO to limit operation to safe
engine speeds. They put out a nice clean square edged pulse. The windlass
is a Lofrans vertical so I figure I could just bolt a little chunk of steel
to the bottom of the shaft and mount a sensor to the bottom of the gearbox.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com