I just discovered something which seems interesting.  It's probably old
hat to y'all (uh, I'm southern:-)), but I could not find information on
this anywhere so I figured I'd post my findings here.

I'm using RB0 external interrupts for the first time, and was not having
good success.  I'm trying to do some interrupt based communications, and
it seemed like I was getting interrupts when I made the pin an output
and pulled it low (it's set up for falling edge interrupts).  So I've
done a good bit of testing by putting out a signal on another pin and
using a scope to read it.  Here is what I found:

1. An interrupt is generated whether the pin is an input or output.

2. The INTF flag is set whenever the pin goes low - even if I explicitly
turn off the RB0/INT interrupt (INTE = 0).  This does not generate an
interrupt.

I can easily work around these things, but it took a while to figure out
what was happening, and I searched all over the internet and through the
Microchip docs and found nothing about this behaviour.  I had assumed
that the INTF flag was only set if the interrupt was enabled, and that
an interrupt was only generated if the pin was an input.  If someone can
point me to information I missed I'd appreciate it very much!

I'm using a PIC16F818, and I don't know if other chips behave the same
way or not.

Moses
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