STACKINT

Function Block - Manages a stack of DINT integers.

Inputs

PUSH : BOOL   Command: when changing from FALSE to TRUE, the value of IN is pushed on the stack
POP : BOOL    Pop command: when changing from FALSE to TRUE, deletes the top of the stack
R1 : BOOL     Reset command: if TRUE, the stack is emptied and its size is set to N
IN : DINT     Value to be pushed on a rising pulse of PUSH
N : DINT      maximum stack size - cannot exceed 128

Outputs

EMPTY : BOOL  TRUE if the stack is empty
OFLO : BOOL   TRUE if the stack is full
OUT : DINT    value at the top of the stack

Remarks

Push and pop operations are performed on rising pulse of PUSH and POP inputs. In LD language, the input rung is the PUSH command. The output rung is the EMPTY output.

The specified size (N) is taken into account only when the R1 (reset) input is TRUE.

ST Language

(* MyStack is a declared instance of STACKINT function block *)
MyStack (PUSH, POP, R1, IN, N);
EMPTY := MyStack.EMPTY;
OFLO := MyStack.OFLO;
OUT := MyStack.OUT;

FBD Language

LD Language

IL Language:

(* MyStack is a declared instance of STACKINT function block *)
Op1: CAL MyStack (PUSH, POP, R1, IN, N)
     LD  MyStack.EMPTY
     ST  EMPTY
     LD  MyStack.OFLO
     ST  OFLO
     LD  MyStack.OUT
     ST  OUT

See also

AVERAGE   INTEGRAL   DERIVATE   LIM_ALRM    HYSTER