ROLPLCopen motion icon

FunctionClosedA 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. - Rotate bits of a register to the left.

Inputs

IN : ANY  register
NBR : DINT Number of rotations (each rotation is 1 bit)

Outputs

Q : ANY   Rotated register

Diagram

RolDiag.gif (1376 octets)

Remarks

Arguments can be signed or unsigned integers from 8 to 32 bits.

In FFLD language, the input rung (EN) enables the operation, and the output rung keeps the state of the input rung. In ILClosed"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 := ROL (IN, NBR);

FBD Language

RolFbd.gif (1241 octets)

FFLD Language

(* The rotation is executed only if EN is TRUE *)
(* ENO has the same value as EN *)
RolLd.gif (1501 octets)

IL Language:

Op1: LDClosed"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  IN
     ROL NBR
     ST  Q

See also

SHL   SHR   ROR