Mascot 3 and Ada

Mascot is a software design method based on a form of a functional and structural design decomposition which is particularly well suited for use in the development of large, distributed, embedded real-time data-processing systems. This paper discusses the problem of using the Mascot design approach when the implementation language is Ada. A particular mapping strategy is developed which, starting from the Mascot graphical design representation, allows Ada package specifications to be derived by the application of a set of simple rules. The bodies are then programmed in standard Ada and may be re-used within other Mascot-derived design structures. The particular problems of maintaining run-time data integrity when coding the bodies of packages to represent the Mascot intercommunication data area (IDA) in Ada are specifically addressed. Finally, the paper discusses the Mascot status progression commands in relation to Ada. (This paper depends heavily on the paper by Simpson [5] published in the same issueof the Software Engineering Journal and should be read in conjuction with it.)