A function calculates a result according to the current value of its inputs. A function has no internal data and is not linked to declared instances. - Get the maximum of two integers.
Inputs
IN1 : DINT First input
IN2 : DINT Second input
Outputs
Q : DINT IN1 if IN1 > IN2; IN2 otherwise
Remarks
In FFLD language, the input rung (EN) enables the operation, and the output rung keeps
the state of the input rung. In IL "Instruction list"
This is a low-level language and resembles assembly language, the first input must be loaded before the
function call. The second input is the operand of the function.
ST Language
Q := MAX (IN1, IN2);
FBD Language
FFLD Language
(* The comparison is executed only if EN is TRUE *)
(* ENO has the same value as EN *)
IL Language:
Op1: LD "Ladder diagram"
Ladder logic is a method of drawing electrical logic schematics. It is now a very popular graphical language for programming Programmable Logic Controllers (PLCs). It was originally invented to describe logic made from relays. The name is based on the observation that programs in this language resemble ladders, with two vertical "rails" and a series of horizontal "rungs" between them IN1
MAX IN2
ST Q (* Q is the maximum of IN1 and IN2 *)
See also
