3.7 Summary

The OSI model is useful for layered development, but various factors like protocol dependencies and performance require the developer to deviate from strict layering. The system decomposition involves breaking up the functionality into modules and tasks. A module can be implemented as multiple tasks, while a task may comprise multiple modules.

The key modules in a communications system are the drivers, protocol modules, and the management/housekeeping modules. The drivers will need to interface with the hardware controllers, including the use of hardware acceleration where appropriate. Protocol modules can be combined into one task or operate as individual tasks.

The modules interact with each other via functional interfaces when they are in the same memory space and via messages if they are in separate memory spaces.



Designing Embedded Communications Software
Designing Embedded Communications Software
ISBN: 157820125X
EAN: 2147483647
Year: 2003
Pages: 126
Authors: T. Sridhar

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