Inputs
IN1 : ANY First input
IN2 : ANY Second input
Outputs
Q : BOOL TRUE if IN1 = IN2
Remarks
Both inputs must have the same type. In FFLD language, the input rung (EN) enables the
operation, and the output rung is the result of the comparison. In IL
"Instruction list"
This is a low-level language and resembles assembly language, the EQ
instruction performs the comparison between the current result and the operand. The
current result and the operand must have the same type.
Comparisons can be used with strings. In that case, the lexical order is used for comparing the input strings. For instance, "ABC" is less than "ZX" ; "ABCD" is greater than "ABC".
Equality comparisons cannot be used with TIME variables. The reason is that the timer actually has the resolution of the target cycle and test can be unsafe as some values can never be reached.
ST Language
Q := IN1 = IN2;
FBD Language
FFLD Language
(* The comparison is executed only if EN is TRUE *)
IL Language:
Op1: FFLD IN1
EQ IN2
ST Q (* Q is true if IN1 = IN2 *)
See also
