Development of a programmable sensor interface for wireless network nodes

This paper reports on the development of a programmable sensor interface board for wireless network sensor nodes to be used in the development of a solution to perform intelligent measurements of the environment in a plant-growing region. The MICA2 mote from Crossbow is selected as the wireless network node. The design of a generic sensor interface board architecture to be embedded in the wireless node is focused upon in this paper. The programmable system on a chip (PSoC) approach proposed, allows the interface to be configured using computational means. Through the development of this sensor interface layer the flexibility and adaptability of connecting both digital and analog, as well as conditioned and unconditioned sensors has been achieved. Different sensors can be connected to the mote through the PSoC interface, enabling the mote to discover any type of sensor as a plug and play device. The paper also describes a power supply board that has been designed to enable the mote to be functional for longer period of time. This board also enables sensors, which require non-standard voltage supply to be integrated into the system.