Axis

Namespace

ZEquipment

Implements

IObject

IBootable

IError

FUNCTION_BLOCK ABSTRACT Axis IMPLEMENTS ZCore.IObject, ZCore.IBootable, ZCore.IError

This class implements common behaviour of axes, like AxisPlcOpenMc. Methods that are implemented by this object forward their parameters to the actual axis implementation (i.e. AxisPlcOpenMcImpl).

The function block severs two main purposes.

• It is to avoid some code duplication, which would otherwise be needed. And more importantly
• the function block comes with an abstract Simulation property, which dictates all extensions of this function block to implement a logic to switch from a physical axis-instance to a simulated axis-instance, and vice-versa.

Properties

ActualMotionState

PROPERTY ActualMotionState : AxisMotionState

Property Value

AxisMotionState

Booted

PROPERTY Booted : BOOL

Property Value

BOOL

Busy

PROPERTY Busy : BOOL

Use State to find out if the object is busy executing its initialization phase, or it is busy performing an actual sequence.

Property Value

BOOL

Done

PROPERTY Done : BOOL

If the object is in idle state (often mentioned as "the object is not busy and not on error"), this is indicated by this property returning TRUE.

Property Value

BOOL

DriveEnabled

PROPERTY DriveEnabled : BOOL

This property can be used to check if an axis is powered by its drive. On the one hand, after successfully running an enable drive command with EnableDriveAsync(on:=TRUE) it is expected that this property is returning TRUE. On the other hand, after successfully executing EnableDriveAsync(on:=FALSE) it is expected that this property is returning FALSE.

If the STO of a drive is active or not enabled for any other reason, this property returns FALSE as well.

Property Value

BOOL

DrivePowered

PROPERTY DrivePowered : BOOL

This property returns TRUE if the drive itself is powered and can provide power to an axis by calling EnableDriveAsync. If this property returns FALSE usually an emergency-stop is pressed or power is missing for some other reason.

Property Value

BOOL

DriveStateAsString

PROPERTY DriveStateAsString : ZCore.ZString

Returns the current state of the drive as string. The returned string may differ may differ severly between implementations, manufactures and depends if the axis is simulated or not. So, this should only be used for logging, debugging and visualization and not be linked to any logic.

Property Value

ZString

Error

PROPERTY Error : BOOL

Property Value

BOOL

Manufacturer

PROPERTY Manufacturer : ZCore.ZString

Returns the manufacturer name of the axis as human-readable text

Property Value

ZString

Parked

PROPERTY Parked : BOOL

Axes can be parked by calling ParkAsync(on:=TRUE). Parking means that any cyclic methods are skipped after executing a parking sequence. If this property returns TRUE, an axis can be "unparked" by using ParkAsync(on:=FALSE).

Property Value

BOOL

Simulation

PROPERTY Simulation : BOOL

This property has to be overwritten by an actual axis implementation (i.e. AxisPlcOpenMc). It is used to switch the axis from a physical instance (i.e. AxisPlcOpenMcImpl) to a simulated axis-instance (i.e. AxisSimulatedImpl).

Settings this property with TRUE or FALSE takes care of automatically parking the unused axis instance and starting the booting sequence for the axis instance that should be used.

Property Value

BOOL

State

PROPERTY ABSTRACT State : ZCore.ObjectState

Returns the object state of the axis object. This exposes if an object is still in its booting phase, had an error, or is busy executing an async action.

Property Value

ObjectState

Methods

EnableDriveAsync

METHOD EnableDriveAsync (
 [input] startToken : ZCore.IStartToken,
 [input] on : BOOL)

By using this method the power output of a drive to an axis can be enabled (on:=TRUE) or disabled(on:=FALSE), respectively. Calling this method will beforehand automatically trigger the following sequences

• Unlock the drive if it has been locked before (AxisPlcOpenMc only)
• Reset any drive errors if there are still errors, which have not been acknowledged yet
• Write parameters to the drive that have been requested to read or write by using the Parameter property of each specialised axis

Executing this method while the drive is still Busy with another Async command will cause this method to fail. This can be checked by submitting an StartToken as a startToken. Simply pass such an object and Assert it or check for startToken.Error after calling this method.

Inputs

startToken IStartToken

on BOOL

ErrorId

METHOD ErrorId () : UDINT

Returns the error code of the first error source for this object. The method recursively goes down the error stack until the initial source of error of this object can be found. For performance reasons, the error stack is not cleared when the error state is reset. So this method should always used in conjunction with Error.

Returns

UDINT

ErrorMessage

METHOD ErrorMessage () : ZCore.ZString

Returns the error description of the first error source for this object. The method recursively goes down the error stack until the initial source of error of this object can be found. For performance reasons, the error stack is not cleared when the error state is reset. So this method should always used in conjunction with Error.

Returns

ZString

ErrorSource

METHOD ErrorSource () : ZCore.IError

This method returns the direct error source of this object. This method can then be used to retrieve the actual error source by using the method of the returned IError.

Returns

IError

Name

METHOD FINAL Name () : ZCore.ZString

Returns the names of all objects that are used within this axis and were set by calling [SetName](xref:ZEquipment.IAxisBase#SetName].

This method should be used with care. It copies several strings and should be called rarely and that means of course not every cycle, but only at initialization phases.

Returns

ZString

ParametrizeAsync

METHOD ParametrizeAsync (
 [input] startToken : ZCore.IStartToken)

This method executes parametrization to the drive. Parameters to read and write can be set-up by using the Parameter property of each axis. Usually this method doesn't have to be called manually, because most other Async method of an axes are calling this method automatically internally. However, use this method if reading or writing is explicitly required at a specific point in the PLC.

Executing this method while the drive is still Busy with another Async command will cause this method to fail. This can be checked by submitting an StartToken as a startToken. Simply pass such an object and Assert it or check for startToken.Error after calling this method.

Inputs

startToken IStartToken

ParkAsync

METHOD ParkAsync (
 [input] startToken : ZCore.IStartToken,
 [input] on : BOOL)

This method can be used to skip any internal cyclic method. Parking an axes and then "unparking" it will automatically execute a booting sequences, where the PLC variables are reinitialized. Parking is usually needed for drives that are optional for a machine and can be hotplugged.

Executing this method while the drive is still Busy with another Async command will cause this method to fail. This can be checked by submitting an StartToken as a startToken. Simply pass such an object and Assert it or check for startToken.Error after calling this method.

Inputs

startToken IStartToken

(optional) object to check if the method was executed successfully - may be 0

on BOOL

RebootAsync

METHOD ABSTRACT RebootAsync (
 [input] startToken : ZCore.IStartToken)

Reboot of the axis, which means that the internal state is switched back to Booting. In practice, this switches the axis' fieldbus back to PREOP, writes all parameters to the drive and then switches back to OP. Internally this is achieved by parking the axis and then unparking it.

Inputs

startToken IStartToken

pass an StartToken instance here to check if the call was successfully executed

RegisterListener

METHOD ABSTRACT RegisterListener (
 [input] listener : REFERENCE TO AxisListenerSequence) : REFERENCE TO AxisListenerSequence

This method called internally whenever an AxisListenerSequence is constructed to register the listener with this axis. Listeners, registered with an axis, are automatically called before and after movements, see AxisListenerType and ListenerState and even during the actual sequence is running

An axis holds a linked list for all listeners that are registered with it. This method returns a reference to the previous listener such that AxisListenerSequence may add itself to the linked list.

Inputs

listener REFERENCE TO AxisListenerSequence

Returns

REFERENCE TO AxisListenerSequence

ResetErrorAsync

METHOD ResetErrorAsync (
 [input] startToken : ZCore.IStartToken)

By using this method any remaining unacknowledged errors on the drive are reset. Usually this method doesn't have to be called manually, because most other Async method of an axes are calling this method automatically internally. However, use this method if resetting the error manually is required for some reason.

• Unlock the drive if it has been locked before (AxisPlcOpenMc only)
• Write parameters to the drive that have been requested to read or write by using the Parameter property of each specialised axis

Executing this method while the drive is still Busy with another Async command will cause this method to fail. This can be checked by submitting an StartToken as a startToken. Simply pass such an object and Assert it or check for startToken.Error after calling this method.

Inputs

startToken IStartToken

(optional) object to check if the method was executed successfully - may be 0

StopAsync

METHOD StopAsync (
 [input] startToken : ZCore.IStartToken)

By using this method the drive will stop with the quickstop profile (regarding jerk, acceleration and deceleration), usually this profile is quicker than the normal position profile, which is used for normal movement profiles and sometimes also for halt. Calling this method will beforehand automatically trigger the following sequences

To check if the method could be started successfully pass such an StartToken as a startToken. Then Assert this object or check for startToken.Error. However, usually StopAsync can always be called, only some very specific implementations may behave differently. In doubt, refer to the documenation of a specific implementation.

Note

If an ongoing task was started with an ExecutionToken as the token parameter (e.g. _axis.AxisName.MoveAbsolutAsync(THIS^) in a Sequence), it gets informed (aborted), if not the same ExecutionToken is used here with this call.

Inputs

startToken IStartToken

(optional) object to check if the method was executed successfully - may be 0

TraceErrorStack

METHOD TraceErrorStack (
 [input] trace : ZCore.IErrorTrace)

This method is used internally when recording an error trace.

Inputs

trace IErrorTrace