The only question I have left is what is the current draw on the empegs switched Ignition input, and what is it's threshold voltage?

The sense input is current limited with, from memory, about 4K7 ohms, which at
the nominal 13.8v battery voltage is around 3mA. The voltage threshold is
determined by a resistive divider, among other things. I think that it would work,
just, at 8.5v in, maybe down to around 7.5v, but I'm too tired to dig out the circuit
diagrams and check the values right now.

I've been hacking away at ARM7500 assembler all day, and I want to go to bed
now.

Patrick.

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