Pulse Falling Edge Contact

Pulse falling edge (negative) contacts enable a Boolean operation between a connection line state and the falling edge of a Boolean variable.
ldr_pfect1
Left Connection
Right Connection
The state of the connection line on the right of the contact is set to TRUE when the state of the connection line on the left is TRUE, and the state of the associated variable falls from TRUE to FALSE. The state is reset to FALSE in all other cases.
Example
ldr_pfect2
(* ST Equivalence: *)
output1 := input1 AND (NOT (input2) AND input2prev);
(* input2prev is the value of input2 at the previous cycle *)
Provide Feedback
Have questions or feedback about this documentation? Please submit your feedback here.
Normal