Polybench® Reference
Starts data processing on all components, or all components that use the specified SyncID.

START

Overview

The START action is used to start processing data. It is the same action that is performed when you press the Start button in the toolbar from Polybench Designer.

An Action may use a Value and an Address
Value: synchronization identifier (user defined text or number, SyncID) to decide which components should be started.
Address: empty.

Details

Value

Leave this empty to start all components that perform some autonomous processing, such as file replay and device operators.
You may also specify a SyncID value that is used by some of the components in your project, to only start those components.

Address

Not used.

Background information

This is a broadcast event that Polybench sends to all or a group of objects in the system, to indicate that data processing can start. Most of the operators do not need this information, because they act as data-slaves, that is, they only process samples that come in via there inputs. But some operators, such as data sources (e.g. an acquisition device) will use this event to start their operation.
Together with the START Action, a synchronization identifier may be transmitted. This allows operators to choose if they have to react on the stop call. Operators that allow this choice, will offer a property that is called SyncID. If and how an operator reacts on a START Action is specified for the operator.

Starting is synchronized with data processing, that is, if a START action is performed, data processing is halted and all objects receive the start command before the next sample is being processed.

The oposite Action is the STOP Action ("STOP").
After calling the START action, some components may issue the STARTING Action ("STARTING") to indicate that they are in the start-up process. After that thay may issue a STARTED action ("STARTED") to indicate that starting was successful.

Synchronous or asynchronous

This action is performed synchronously with data processing. If an action is asynchronous, it is performed only after all synchronous actions in a sequence have been called. A synchronous action is performed immediately.