Hardware Abstraction Architecture of TInyOS

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Hardware Abstraction Architecture of TInyOS

The Hardware Abstraction Architecture of TinyOS has three layers..

1.Hardware Presentation Layer:
  • It is the lowest layer.
  • It provides the lowest level access to the hardware, and provides wrappers around lowest level tasks,such as setting registers with higher level software calls.
  • Components in this layer are not expected to be used from user program as any functionality they provide should be exposed by higher levels above it.
  • Components should be efficient,because many higher level components may call it simultaneously.

    2.Hardware Adaptation Layer:
  • It is above the Hardware Presentation Layer.
  • Contains most of the platform code.
  • Exposes one or more components for each piece of functionality the mote provides.
  • HAL components provide advanced functionality of the program at the expense of programs using them become platform-specific.

3.Hardware Interface Layer:
  • The interfaces and components in this layer are expected to be provided by each platform.
  • Majority of the code in this layer is just mapping between the standard interface and the interface which are defined by the HAL.
  • If a program uses a components in the HIL,then it will run correctly on al platforms without changing any code.      

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