MCV_ChgParamValue

Change parameter value

To prevent problems caused by incorrect parameterisation, this block does not change the original parameter set but creates a copy and writes the changes to it. The copy is referred to as the work list in this documentation.

The original parameter set need not correspond to the currently active parameter data record. It is selected by specifying its identifier at the ”NcParamSetIDIn” input.

Notice

This function block is not available in TwinCAT systems..

Notice

The modified parameters in the work list are only adopted by the ISG-MCP and only take effect after they are activated by the MCV_ActivateParamChg function block.

Block diagram

FB parameters

VAR_IN_OUT
Variable name	Data type	Description
Axis	AXIS_REF	Axis reference

VAR_INPUT
Variable name	Data type	Description
Execute	BOOL	A change of parameter value is executed on a rising edge.
NCListTypeIn	STRING	Identifier for parameter or list type e.g. “ACHS_MDS“
NCParamSetIDIn	UINT	Number of the parameter set where the parameter value is to be changed.
NCParamIdentIn	STRING	Identifier of parameter to be changed, e.g. “knngr.swe_pos“
NCParamValueIn	STRING	New value of the parameter..
VAR_OUTPUT
Variable name	Data type	Description
Valid	BOOL	Is TRUE when the parameter set change was executed successfully.
Busy	BOOL	Is TRUE if the FB is still active.
NCListTypeOut	STRING	Identifier for parameter or list type e.g. “ACHS_MDS“
NCParamSetIDOut	UINT	Number of the parameter set where the parameter value was/is to be exchanged.
NCParamIdentOut	STRING	Identifier of parameter to be changed e.g. “knngr.swe_pos“
NCParamValueOut	STRING	New value of the parameter..
NCWarning	BOOL	Is TRUE if a warning occurred in the ISG-MCP.
NCError	BOOL	Is TRUE if an error occurred in the ISG-MCP while a parameter value is changed.
NCErrorCode	UDINT	Error code of the error or warning occurring in the ISG-MCP.
Error	BOOL	Is TRUE if the FB is in error state. The change in the parameter value was not executed successfully.
ErrorID	WORD	Error code

¹) Availability is dependent on the MCE used.

Behaviour of the FB:

The FB is in an error state if "Error" = TRUE. The parameter was not written to the work list. An error occurred either in the function block itself or in the ISG-MCP. The "NCError" output parameter indicates whether an error occurred in the ISG-MCP.
A frequent cause of ISG-MCP errors are absent write access or a write-protected work list since in these cases, a work list was not created or a parameter cannot be written.