Edge triggering?

[JonCyphers]

I thought I came across this somewhere earlier and can't find it now, but I'll ask for the preferred method also.

Our EAS will give us a closure on 'Encoder Active', I wired that to pull Input 1 of port 8 of one of our GPIO's low.
What I would like to do is when it goes low have it fire three routing instructions (HD1, HD2, and HD3 switch to EAS input), and when it goes back to high to switch those three outputs back to where they came from (which could be different depending on the time of day the EAS goes off).

But I don't want to make Pathfinder think it's in an endless loop by just telling it, when this IO is high do this...otherwise all day long wouldn't it try to fire that command?

What's the preferred method of doing this, I'm sure it's come up before.

Thanks!
jon

[DanBays]

Jon,
The easiest way to do this is with a stack event. Set the qualifier to be a GPI on the desired port and pin and set it for low. Set the Action if qualifiers are met to be the route to EAS, and the Action if qualifiers not met to be the route back to the usual source.

This will not cause an endless loop in Pathfinder. The stack event system is based on event changes. It only analyzes an event if something in one of the qualifiers changes.

In other words in the event above, Pathfinder places a watch on the GPI. If it changes then the event is analyzed to see if actions need to be taken. But if it does not change, then Pathfinder does not do anything.

[JonCyphers]

Thanks Dan that should take care of it. I appreciate the help!
jon