BackgroundTask (FB)¶

FUNCTION_BLOCK FINAL BackgroundTask EXTENDS CBML.LConC IMPLEMENTS IBackgroundTask

Encapsulates all the details of managing a iec task in the context of the runtime system.

A running background task can be controlled via the methods of IBackgroundTask.

Note

Watchdog Sensitivity:

If the actual cycle time of a task exceeds the currently udiWatchdogTime, the currently defined usiWatchdogSensitivity value is taken into account:

Sensitivity 0, 1 => exception in cycle 1
Sensitivity 2 => exception in cycle 2
Sensitivity n => exception in cycle n
Single Timeout => Exception if the actual cycle time is longer than usiWatchdogSensitivity x udiWatchdogTime.

InOut:

Scope	Name	Type	Comment	Inherited from
Input	`xEnable`	`BOOL`	`TRUE`: Activates the defined operation `FALSE`: Aborts/resets the defined operation	LConC
Output	`xBusy`	`BOOL`	`TRUE`: Operation is running	LConC
Output	`xError`	`BOOL`	`TRUE`: Error condition reached	LConC
Input Const	`tgTaskGroup`	TASK_GROUP
	`anAppName`	APP_NAME
	`tnTaskName`	TASK_NAME
	`usiTaskPrio`	`USINT`
	`udiTaskInterval`	`UDINT`	Taskinterval in µs
	`xWatchdogEnabled`	`BOOL`	`TRUE` => Watchdog will be enabled
	`udiWatchdogTime`	`UDINT`	Watchdog Time in µs
	`usiWatchdogSensitivity`	`USINT`	Defines the behavior of a task watchdog when exceeding the `udiWatchdogTime`. (See note above)
Input	`itfParams`	`SHD.ISharedQueue`	Parameter Queue feeding the IAsyncActionProvider.AsyncAction
Input	`itfAction`	IAsyncActionProvider	Specifies the action executed in the context of this background task
Output	`eErrorID`	ERROR	If `xError` is `TRUE` => Information about the current error condition
	`itfResult`	`SHD.ISharedArea`	Current states and results of the background task
	`dwCurrentCycleTime`	`DWORD`
	`dwAverageCycleTime`	`DWORD`
	`dwMaxCycleTime`	`DWORD`
	`dwMinCycleTime`	`DWORD`
	`dwCycleCounter`	`DWORD`

Methods:

SetInitialValue

TaskDisableScheduling

TaskDisableWatchdog

TaskEnableScheduling

TaskEnableWatchdog

TaskResetStatistics

Structure: