I have two secure parameters which I want to use to trigger one digital output, when either parameter goes 'false' I want the output to trigger, but I also want it to trigger if one of the parameters is already false and the other becomes false and on any transition from true to false I want the output to re-trigger. Any ideas? Thanks.
Something like this?
Would you need the DO to stay on and then go off and back on a new FALSE?
In reply to Travis Neale:
Hi Travis,
Yes, the DO would need to stay on when any false condition is in, also if one parameter were false and the DO triggered, if the other parameter were to go false I need it to re-trigger. Plus any subsequent true to false transitions on either parameter would need to re-trigger the DO.
If no false conditions the DO needs a '1' to be healthy.
In reply to Mambo:
Let me make sure I'm understanding this right. You want the DO to be a 1 when either or both are false, a 1 when neither are false and then you want the DO to go from 1 to 0 and back to 1 when one of the parameters transitions to false. Is that correct? If that is the case you can put a NOT block in front of the DO above to accomplish that. The DO would flip off and back on with any false transition. If the transition is too quick you can add a timed pulse block after the NOT.
I want the DO to have a value of '1' if both parameters are true.
If either or both are false the DO will have a value of '0'.
I think the main problem is re-triggering the DO when the second parameter goes false (ie, one parameter is already false and then the other goes false also.)
Try this. The AND block should keep it 1 when both are true, and 0 when either is false. The OR2 block will retrigger it's out to 1 when either Negative Edge Triggers fire.