Flexible hardware abstraction for wireless sensor networks

We present a flexible hardware abstraction architecture (HAA) that balances conflicting requirements of wireless sensor networks (WSNs) applications and the desire for increased portability and streamlined development of applications. Our three-layer design gradually adapts the capabilities of the underlying hardware platforms to the selected platform-independent hardware interface between the operating system core and the application code. At the same time, it allows the applications to utilize a platform´s full capabilities-exported at the second layer, when the performance requirements outweigh the need for cross-platform compatibility. We demonstrate the practical value of our approach by presenting how it can be applied to the most important hardware modules that are found in a typical WSN platform. We support our claims using concrete examples from existing hardware abstractions in TinyOS and our implementation of the MSP430 platform that follows the architecture proposed in this paper.