Thanks Dana, exactly what I had in mind, using 200 ohms on R1, NAND gate sprang to life beautifully, had 4.4v out of the opto, getting 12v out of the MOSFET driver chip and 12v going in to the MOSFET gate.

So I think the board will run a motor now. I need to clean up some stuff before I do that. My diode isn't flashing however and has something to do with an open pin on my board bottom. I am missing something.
There is no R7 diode step-down resistor on the OSHPark board?!?!?

You can see I have an open pin + to diode at the red arrow. I traced in where R7 goes.

I have been meaning to post a question about that open pin.
But better to post an answer. 




5v still good, still loads a program and talks to the PC. Ordered Some Atmega chips for a few dollars. Just too excited about building my AMC. That ruggedino sounds better and better. They sure got me nailed, making mistakes. They made that bullet proof. For power reversal, lapped in a blocking diode. Won't get me again! That's what they put in the ruggedino too.
But at least it doesn't start out at 13v like the other, but stays at a higher voltage. Seems more stable. Maybe I can use one of those cell phone chargers?
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