Trigger

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Triggers are used in the logic tables.

These must not be mixed with normal signals.

A trigger signal is "now". This is neither 1 nor 0. Rather, it can be described with an extremely quick change from 0 to 1 and back again.

If something like that is required, then only a logic table helps that sets a bool constant to 1 with a trigger and as quickly as possible to 0 again. That works with constant bool 1, then a trigger high value. It strikes immediately. Then use the trigger result to control a boolean constant with 0. You can then use the 1 or the 0 value. However, this is not the normal way and does not always lead to the goal.

Triggers are not a number and never will be. In older versions of PLC Engine Collect there was a bug that a trigger signal could be used as a bool and therefore did not work or only worked by chance. Because bool is a state that lasts. A trigger, ie "now" is an arbitrarily short signal.

All trigger inputs that are connected to a trigger output save this "now". All other inputs of course also save the pending value, but the processing is different. A trigger as a bool (bug) randomly returns sometimes 1 and sometimes 0. The chance depends solely on the signal runtime. This is the classic mistake, where you spend hours looking for the cause.