Motion Library - Comparator

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• • For a Comparator function example, see Usage example of Comparator Functions
  • For a description of the this pipe block and its parameters, see Pipe Blocks Description

Name	Description	Return type
MLCompCheck	Checks if the reference of a comparator Pipe Block has been crossed. Returns TRUE if the reference has been crossed	BOOL
MLCompInit	Initializes a comparator Pipe Block with user-defined settings	BOOL
MLCompReadRef	Returns the reference position of a comparator block	None
MLCompReset	Clears the Transition Flag of a comparator Pipe Block	BOOL
MLCompWriteRef	Sets the reference position of a comparator block	BOOL

 

MLCompCheck

Description

Check if the reference of a comparator Pipe Block has been crossed. Returns the Transition Flag of a comparator object, which turns TRUE if the input position to the comparator is greater or equal to the reference. The Comparator Transition Flag stays TRUE until it is reset.

Figure 7-90: MLCompCheck

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• This function or function block returns cached data. See Programming a Dual Core Controller for more information.

Arguments

Input

BlockID	Description	ID number of an initiated Comparator object
	Data type	DINT
	Range	[-2147483648, 2147483648]
	Unit	n/a
	Default	—

Output

Default (.Q)	Description	Returns TRUE if reference position of the Comparator object has been crossed See more details here
	Data type	BOOL
	Unit	n/a

Return Type

BOOL

Related Functions

MLCompReset

MLCompWriteRef

MLCompReadRef

Example

Structured Text

//Check if Comparator Reference has been reached bCrossed := MLCompCheck( PipeNetwork.MyComp );

Ladder Diagram

 

Function Block Diagram

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MLCompInit

Description

Initializes a comparator Pipe Block for use in a PLC"Programmable Logic Controller" A Programmable Logic Controller, PLC, or Programmable Controller is a digital computer used for automation of industrial processes, such as control of machinery on factory assembly lines. Used to synchronize the flow of inputs from (physical) sensors and events with the flow of outputs to actuators and events Program. FunctionA 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. block is automatically called if a Comparator Block is added to the Pipe Network, with user-defined settings entered in the Pipe Blocks Properties screen.

The Transition Flag of a comparator object turns TRUE if the input position to the comparator is greater or equal to the reference. The Comparator Transition Flag stays TRUE until it is reset.

If the input ThroughZero is set to TRUE, system must cross zero and then the reference position before the Transition Flag is set. If ThroughZero is FALSE, Transition Flag is set immediately if the input pipe position is greater or equal to the Reference value.

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• Comparator objects are normally created in the Pipe Network using the graphical engine. Then you do not have to add MLCompInit function blocks to their programs. Parameters are entered directly in pop-up windows, and the code is then automatically added to the current project.

Arguments

Input

BlockID	Description	ID number of a created Comparator Pipe Block
	Data type	DINT
	Range	[-2147483648, 2147483648]
	Unit	n/a
	Default	—
ModuloPosition	Description	Value of the period of a cyclic system
	Data type	LREAL
	Range	—
	Unit	User unit
	Default	—
ThroughZero	Description	When TRUE, system must cross zero and then the reference position before the Transition Flag is set. If FALSE, Transition Flag is set immediately if the input pipe position is greater then or equal to the Reference value.
	Data type	BOOL
	Range	0, 1
	Unit	n/a
	Default	—
Reference	Description	Set the reference position in the new Comparator object
	Data type	LREAL
	Range	—
	Unit	User unit
	Default	—

Output

Default (.Q)	Description	Returns TRUE when function starts to execute See more details here
	Data type	BOOL
	Unit	n/a

Return Type

BOOL

Related Functions

MLBlkCreate

MLCompCheck

MLCompReset

MLCompWriteRef

Example

Structured Text

      //Initiate a created Comparator Block named “MyComp” to:
//   Modulo of 360
//   Require the input position to first cross 0 before the
//      MLCompCheck output is triggered
//   Input compared position to 45
      
MyComp := MLBlkCreate( 'MyComp', 'COMPARATOR' );
MLCompInit( MyComp, 360.0, TRUE, 45.0 );

Ladder Diagram

 

Function Block Diagram

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MLCompReadRef

Description

Returns the reference position of a comparator block. The Transition Flag of a comparator object turns TRUE if the input position to the comparator is greater or equal to the reference. The Comparator Transition Flag stays TRUE until it is reset.

Arguments

Input

BlockID	Description	ID number of an initiated Comparator object
	Data type	DINT
	Range	[-2147483648, 2147483648]
	Unit	n/a
	Default	—

Output

Reference	Description	Returns the current reference position of the Comparator object
	Data type	LREAL
	Unit	User unit

Related Functions

MLCompWriteRef

MLCompReset

MLCompCheck

Example

Structured Text

//Return the Comparator Reference value
CompRef := MLCompReadRef( PipeNetwork.MyComp );

Ladder Diagram

 

Function Block Diagram

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MLCompReset

Description

Clear the Transition Flag of a comparator Pipe Block. The Transition Flag of a comparator object turns TRUE if the input position to the comparator is greater or equal to the reference. The Comparator Transition Flag stays TRUE until it is reset.

Arguments

Input

BlockID	Description	ID number of an initiated Comparator object
	Data type	DINT
	Range	[-2147483648, 2147483648]
	Unit	n/a
	Default	—

Output

Default (.Q)	Description	Returns TRUE when function starts to execute See more details here
	Data type	BOOL
	Unit	n/a

Return Type

BOOL

Related Functions

MLCompCheck

MLCompReadRef

MLCompWriteRef

Example

Structured Text

//Clear the Transition Flag of a Comparator object
MLCompReset( PipeNetwork.MyComp );

Ladder Diagram

Function Block Diagram

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MLCompWriteRef

Description

Set the reference position of a comparator block. The Transition Flag of a comparator object turns TRUE if the input position to the comparator is greater or equal to the reference. The Comparator Transition Flag stays TRUE until it is reset.

If the input ThroughZero is set to TRUE, system must cross zero and then the reference position before the Transition Flag is set. If ThroughZero is FALSE, Transition Flag is set immediately if the input pipe position is greater then or equal to the Reference value.

Figure 7-91: MLCompWriteRef

Arguments

Input

BlockID	Description	ID number of an initiated Comparator object
	Data type	DINT
	Range	[-2147483648, 2147483648]
	Unit	n/a
	Default	—
ThroughZero	Description	When TRUE, system must cross zero and then the reference position before the Transition Flag is set. If FALSE, Transition Flag is set immediately if the input pipe position is greater then or equal to the Reference value.
	Data type	BOOL
	Range	0, 1
	Unit	n/a
	Default	—
Reference	Description	New reference position to set in the selected Comparator object
	Data type	LREAL
	Range	—
	Unit	User unit
	Default	—

Output

Default (.Q)	Description	Returns TRUE when function starts to execute See more details here
	Data type	BOOL
	Unit	n/a

Return Type

BOOL

Related Functions

MLCompCheck

MLCompReadRef

MLCompReset

Example

Structured Text

//Set the Comparator Reference value MLCompWriteRef( PipeNetwork.MyComp , TRUE , 45 );

Ladder Diagram

Function Block Diagram

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Usage example of Comparator Functions

When you call the MLCompWriteRef function, the output for MLCompCheck becomes True as soon as the input value reaches the reference.

The same function can also be called for a cyclic input value.

When the THROUGH_ZERO parameter is set to YES, the output for MLCompCheck becomes True as soon as the input value reaches the reference, but not before it has passed through zero.

Figure 7-92: Comparator Functions Usage

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