Short summary

Name	`CTUD_ULINT`
→POU type	→function block
Category	IEC-block, Counter
Conform to →IEC-standard	no restrictions
Graphical interface
Available since	version 1.19.0 (for logi.CAD 3)

Functionality

The block is an up- and down-counter (for ULINT values).

If there is a positive →edge at input CU, the counter is activated and increments the counter value by 1. If there is a positive edge at input CD, the counter is activated and decrements the counter value by 1.
If input R is →turned on, the counter value is reset to value 0. If input LD is turned on, the counter value is reset to the value entered at PV. If this value is reached or exceeded when counting up, output QU is set to value TRUE (or an equivalent). If the counter value reaches or falls below 0 when counting down, output QD is set to value TRUE (or an equivalent).
The incrementing is stopped, if the upper limit of ULINT (= value 18,446,744,073,709,551,615) is reached. The decrementing is stopped, if the lower limit of ULINT (= value 0) is reached.
Output CV returns the current counter value of the block.

In-/outputs

	Identifier	→Data type	Description
Inputs:	`CU`	`BOOL`	increment in case of positive edge
	`CD`	`BOOL`	decrement in case of positive edge
	`R`	`BOOL`	flag for reset to value `0`
	`LD`	`BOOL`	flag for reset to value of `PV`
	`PV`	`ULINT`	limiting value for counting up
Outputs:	`QU`	`BOOL`	flag showing whether limiting value is reached or not
	`QD`	`BOOL`	flag showing whether value `0` is reached or not
	`CV`	`ULINT`	current counter value

Input EN and output ENO are available when →calling the block. See "Execution control: EN, ENO" for information on input EN and output ENO.

See:

"Blocks for safe logic" whether this block is supported for developing safety-relevant applications.
"Highlighting safe logic in the FBD-editor" for the effects when using the block as a block for safe logic .

Example for usage within ST-editor

PROGRAM Test
    VAR
        myCTUD           : CTUD_ULINT;
        StartUpCnt       : BOOL;
        StartDownCnt     : BOOL;
        ResettoZero      : BOOL;
        ResettoValueOnPV : BOOL;
        outUp            : BOOL;
        outDown          : BOOL;
        counter          : ULINT;
    END_VAR
 
    myCTUD(CU := StartUpCnt, CD := StartDownCnt, R := ResettoZero, LD := ResettoValueOnPV, PV := 10, QU => outUp, QD => outDown, CV => counter);
    (* Instance of block 'CTUD_ULINT' is called: The up-counter is activated, when 'StartUpCnt' is 'TRUE'. The down-counter is activated, when 'StartDownCnt' is 'TRUE'. *)
    (* The value for counting is reset to '0', when 'ResettoZero' is 'TRUE'. It is reset to '10', when 'ResettoValueOnPV' is 'TRUE' *)
    (* The limiting value for counting up is '10'. *)
    (* Appropriate variables access the outputs. *)
END_PROGRAM

When creating your application within the ST-editor, enter a call of a block by typing the text as requested by the syntax or use Content Assist.