20 - Modifications from previous releases
20.1 - Semaphore manipulation
20.1.1 V1.0 to V1.1The semaphore take now returns a status that indicates if the take attempt timed out or was successfull. The semaphore lifeline gets grayed when the semaphore is unavailable.
20.2 - Object orientation
20.2.1 V1.1 to V1.2There has been an error in the object orientation chapter: it is not possible to declare a process class or a block class in a block class definition diagram.
20.2.2 V1.2 to V2.0
- UML class diagram has been introduced
- UML deployment diagram has been introduced
- Object creation symbol introduced in the behavior diagram
20.2.3 V2.1 to V2.2
20.3 - Messages
20.3.1 V1.1 to V1.2
- Messages now needs to be declared.
- Message parameters are now typed with C types.
- Parameter length can be omited if the parameter is structured. Then the length is implicitly the sizeof the parameter type.
- The VIA concept has been introduced.
20.3.2 V2.0 to V2.1
20.4 - MSC
20.4.1 V1.1 to V1.2
20.4.2 V2.2 to V2.3
- Inline expressions support added.
- Property Sequence Charts (PSC) support added.
- Change in MSC diagram DTD for textual representation.
20.5 - Task
20.5.1 V1.2 to V2.0STACK parameter has been added as a parameter when creating a task.
20.6 - Organisation
20.6.1 V1.2 to V2.0Chapters have been re-organized.
20.7 - New concept
20.7.1 V2.1 to V2.2"Composite state" has been introduced