R_TRIG block

Short summary

Name	`R_TRIG`
→POU type	→function block
Category	IEC-block, Edge
Conform to →IEC-standard	no restrictions
Graphical interface
Available since	version 1.4.1 (for Neuron Power Engineer)

Functionality

This block detects a rising edge.

→Turning input CLK on triggers output Q to return value TRUE (or an equivalent) from one execution of the function block to the next. Output Q returns value FALSE (or an equivalent) at the next execution.

Observe:

If the input CLK is connected to value TRUE, output Q returns TRUE after its first execution following a →cold restart. Output Q returns FALSE following all subsequent executions.

In-/outputs

	Identifier	→Data type	Description
Inputs:	`CLK`	`BOOL`	current value
Outputs:	`Q`	`BOOL`	flag showing rising edge detection

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

    Activator : R_TRIG;

    Out       : BOOL;

    Trigger   : BOOL;

  END_VAR

  Activator(CLK := Trigger, Q => Out);

  (* Instance of block 'R_TRIG' is called. *)

  (* Input 'CLK' gets value from 'Trigger' variable. *)

  (* Output 'Q' returns TRUE for one cycle, if 'Trigger' was FALSE and is now TRUE. *)

  (* Variable 'Out' accesses the output 'Q'. *)

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.