MC_ReadStatus
MC_ReadStatus determines the current operating state of an axis and signals it at the function block outputs.
The updated operating state is additionally stored in the Status output data structure and in the Axis.Status axis data structure. This means the operating state only has to be read once at the start of each PLC cycle and can then be accessed via Axis.Status.
The Axis variable (type AXIS_REF) already includes an instance of the function block MC_ReadStatus. This means that the operating state of an axis can be updated at the start of a PLC cycle by calling up Axis.ReadStatus. |
Sample:
PROGRAM MAIN
VAR
Axis1 : AXIS_REF
END_VAR
(* call the read status function *)
Axis1.ReadStatus;
Inputs
VAR_INPUT
Enable : BOOL;
END_VAR
Enable | As long as Enable = TRUE, the axis operating state is updated with each call of the function block. |
Outputs
VAR_OUTPUT
Valid : BOOL;
Busy : BOOL;
Error : BOOL;
ErrorId : UDINT;
(* motion control statemachine states: *)
ErrorStop : BOOL;
Disabled : BOOL;
Stopping : BOOL;
StandStill : BOOL;
DiscreteMotion : BOOL;
ContinuousMotion : BOOL;
SynchronizedMotion : BOOL;
Homing : BOOL;
(* additional status *)
ConstantVelocity : BOOL;
Accelerating : BOOL;
Decelerating : BOOL;
(* status data structure *)
Status : ST_AxisStatus;
END_VAR
Valid | Indicates that the axis operating state indicated at the other outputs is valid. |
Busy | Indicates that the function block is active. |
Error | Becomes TRUE if an error occurs. |
ErrorID | If the error output is set, this parameter supplies the error number |
ErrorStop | Axis status according to the PlcOpen state diagram |
Disabled | Axis status according to the PlcOpen state diagram |
Stopping | Axis status according to the PlcOpen state diagram |
StandStill | Axis status according to the PlcOpen state diagram |
DiscreteMotion | Axis status according to the PlcOpen state diagram |
ContinousMotion | Axis status according to the PlcOpen state diagram |
SynchronizedMotion | Axis status according to the PlcOpen state diagram |
Homing | Axis status according to the PlcOpen state diagram |
ConstantVelocity | The axis is moving with constant velocity |
Acceleration | The axis accelerates. |
Decelerating | The axis decelerates. |
Status | Extended status data structure with additional status information. |
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.