> So your ADC threshold is 131 or so.  Is that what you wanted?

Hi Andrew, yes it is. You've done it in a slightly different way to
what I've been experimenting with. One approach I tried, and I
think I may have done a little too much thinking about this and
lost focus, was to think of all numbers in terms of millivolts. The
sensor interfaces I'll be using have their limits, so at least that part
of it isn't open-ended. So, taking the battery monitor as an example,
say I used a 3:1 divider, therefore 5V to the A2D represents
15V, which would be a reasonable limit for a 12V battery

If the user wants the PIC to send a message when the voltage
reaches 13.5V, this would need to be stored as a comparison
figure of 1023 / (13.5 /3)

I admit again, maybe my thinking has gone fuzzy. It seemed
simple enough to start with. I was hoping that trying to explain
it to someone else and then perhaps discussing it might help
me get a better grip on what seems so slippery. It could be
that I'm getting bogged down because I've over-complicated it

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