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| Contents | Index |
Asynchronous
The Asynchronous Task Specification block, in combination with a root-level Inport block, allows for an asynchronous function-call input to a model reference.
To implement this feature, place this block at the output port of each root-level Inport block that outputs a function-call trigger. On the Signal Attributes pane of the Inport block, select Output function call to specify that the Inport block accepts function-call signals. Then use the Asynchronous Task Specification blocks to specify the asynchronous task parameters associated with the respective Inport blocks.
This specification does not apply to the Asynchronous Task Specification block; the block accepts only function-call signals.
The Function Block Parameters dialog box of the Asynchronous Task Specification block appears as follows:
Specifies the priority of the asynchronous task calling the destination function-call subsystem. The priority must be a value that generates relevant rate transition behaviors.
Default: 10
You can enter an integer or [].
If you specify an integer for an Asynchronous Task Specification block that resides in a model reference, then the initiator in the top model must have the same integer value for its priority.
If you specify [] for an Asynchronous Task Specification block that resides in a model reference, then the initiator in the top model can have any priority. For this case, the rate transition algorithm is conservative (not optimized), assuming that the priority is unknown but static.
This block has only one parameter.
Parameter: TaskPriority
Value: integer
To create an asynchronous model reference containing a Function-Call and an Asynchronous Task Specification block, you must follow the procedure outlined in Convert an Asynchronous Subsystem into a Model Reference. One of the steps requires that you make several changes to configuration parameters.
Additional configuration parameters that require attention are the solver Type and the Fixed step size (fundamental sample time) on the Solver pane. Both the top model and the model reference must use a fixed-step solver. Moreover, the submodel must have a fundamental sample time that is an integer multiple of the fundamental sample time of the top model.
This root-level model uses the Inport block with the Asynchronous Task Specification block to allow a function-call input signal to a model reference. The priority is set to 10.
The Asynchronous Task Specification block must immediately follow the Inport block. Also, no branch can emanate from the signal connecting the Inport block to the Asynchronous Task Specification block.
For this model, if the Asynchronous Task Specification block is set to the default value of 10, then the Async Interrupt block must also have a priority of 10.
Whereas, if the priority of the Asynchronous Task Specification block is set to the empty matrix, [], then the Async Interrupt can have any value.
Direct Feedthrough | Yes |
Sample Time | Inherited from the driving block |
Scalar Expansion | N/A |
Dimensionalized | No |
Multidimensionalized | No |
Zero-Crossing Detection | No |
Function-Call Subsystem block
Inport block
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