MC_ReadParameter

MC_ReadParameter 1:

The function block MC_ReadParameter is used to read an axis parameter.

	In this case "axis" refers to the TwinCAT NC axis and not the drive.

Inputs


VAR_INPUT
    Enable          : BOOL;            (* B *)
    ParameterNumber : MC_AxisParameter;    (* B *)
    ReadMode        : E_ReadMode         (* V *)
END_VAR

E_ReadMode MC_AxisParameter

Enable	The command is executed as long as Enable is active.
ParameterNumber	Number of the parameter to be read.
ReadMode	Read mode of the parameter to be read (once or cyclic).

Outputs


VAR_OUTPUT
    Valid   : BOOL;  (* B *)
    Busy    : BOOL;  (* E *)
    Error   : BOOL;  (* B *)
    ErrorID : DWORD; (* E *)
    Value   : LREAL; (* B *)
END_VAR

Valid	The value signaled at the Value output is valid
Busy	The Busy output becomes TRUE when the command is started with Enable and remains TRUE as long as the command is processed. If Busy becomes FALSE again, the function block is ready for a new order.
Error	Becomes TRUE if an error occurs.
ErrorID	If the error output is set, this parameter supplies the error number
Value	Displays the read value.

Inputs/outputs


VAR_IN_OUT
    Axis    : AXIS_REF;
END_VAR

Axis

Axis data structure

The axis data structure of type AXIS_REF addresses an axis unambiguously within the system. Among other parameters it contains the current axis status, including position, velocity or error state.