MC_SetPos

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Function Block - Changes the present actual position of the axis (as reported by MC_ReadActPos) to the position specified by the Position and Mode inputs.

Inputs

Input	Data Type	Range	Unit	Default	Description
Execute	BOOL	FALSE, TRUE	N/A	No default	On the rising edge, request to queue the change to the axis position.
Axis	AXIS_REF	1 to 256	N/A	No default	Name of a declared instance of the AXIS_REF library function. See Axis Name and Number. See AXIS_REF Structure.
Position	LREAL	No range	N/A	No default	Absolute Mode: New Axis Position to replace the present position. Relative Mode: Position offset to apply to present position. Typically used with multi-turn absolute position feedback devices.
Mode	BOOL	FALSE, TRUE	N/A	No default	LOW = Position input is an absolute position. HIGH = Position input is a relative position

Outputs

Output	Data Type	Range	Unit	Description
Done	BOOL	FALSE, TRUE	N/A	Indicates the reference move and position adjustment is complete.
Busy	BOOL	FALSE, TRUE	N/A	Indicates this function block is executing.
Error	BOOL	FALSE, TRUE	N/A	Indicates either: An invalid input was specified. The move was terminated due to an error.
ErrorID	INT	-32768 to +32767		Indicates the error if Error output is high. See PLCopen Function Block ErrorIDs.

Remarks

This function or function block returns cached data.
See Program a Multi-Core Controller.

See Function Blocks - General Rules about how inputs and outputs work.
If a motor is associated with the axis, it does not move when MC_SetPos is executed.
- MC_SetPos does not cause any motion.
- It applies an offset to the command and actual positions.
MC_SetPos sets the accumulated Superimposed distance value for the input axis to 0 (zero).
- See Axis Positions Data for more information.
This function block replaces MC_SetPosition.

This function block starts a motion-related action and stores data for calculations and error checking.
If using a dual-core controller, see Call Function Blocks Multiple Times in the Same Cycle.

Figure 1: MC_SetPos

FBD Language Example

Not available.

FFLD Language Example

This function block finishes immediately.
Because of this, the Done output does not get set to FALSE in a second call to the same MC_SetPos instance unless there is an error.

If the application needs to look for a state change to determine if a particular call to MC_SetPos was successful, then use AND for the rising edge of the Execute input, the Done output, and the inverse of the Error output.

This FFLD Language example shows how this can be done.
In the example, the SetPosSuccessful variable is set to TRUE for one cycle upon a successful call to the MC_SetPos instance.

IL Language Example

Not available.

ST Language Example

            (* MC_SetPos ST example *)
            
Inst_MC_SetPos ( Axis1 , 0, 0 );
//Inst_MC_SetPos is an instance of MC_SetPos function

(* MC_SetPos absolute mode example: Set position value to zero. *)
Inst_MC_SetPos ( Axis1 , 0, 0 );
//Inst_MC_SetPos is an instance of MC_SetPos function

(* MC_SetPos relative mode example: Increase position value by 1000. *)
Inst_MC_SetPos ( Axis1 , 1000, 1 );
//Inst_MC_SetPos is an instance of MC_SetPos function