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Topic Details for Soft Logic

Edge Contact Instructions

Edge contact instructions are a type of Boolean input instruction, and operate in a manner similar to that of the normal Boolean input instructions. The difference is that they are one-shot instructions and output a true for one scan only.

Instruction	Description	# Params	X	Y	C	T	CT	SC
ANDND	AND negative differential	1	X	X	X	X	X	X
ANDPD	AND positive differential	1	X	X	X	X	X	X
ORND	OR negative differential	1	X	X	X	X	X	X
ORPD	OR positive differential	1	X	X	X	X	X	X
STRND	STORE negative differential	1	X	X	X	X	X	X
STRPD	STORE positive differential	1	X	X	X	X	X	X

Edge contact instructions can be categorised as "positive differentiate" and "negative differentiate" instructions. "Positive differentiate" instructions are true for one scan when the logic stack makes a false to true transition. "Negative differentiate" instructions are true for one scan when the logic stack makes a true to false transition.

The address used as a parameter is used for an AND, OR, or STORE the operation. It is not necessary to specify an address to store the one shot state, as the instruction stores this information automatically internally.

Example:


	NETWORK 1
	STR X1
	ANDPD C1
	OUT Y1
	
	NETWORK 2
	STR X2
	ANDND C2
	OUT Y2
	
	NETWORK 3
	STR X3
	ORPD C3
	OUT Y3
	
	NETWORK 4
	STR X4
	ORND C4
	OUT Y4
	
	NETWORK 5
	STRPD X5
	OUT Y5
	
	NETWORK 6
	STRND X6
	OUT Y6

Ladder Examples

The following shows examples in ladder format. Each example shows the IL code as comments, followed by the ladder equivalent.

edge example 1 edge example 2