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The main issue that is addressed in this book is to use reactive objects as an approach for programming embedded systems. A real project in robotics is considered and the goal in this project is to develop a radio communication device driver based on a real- time kernel, called "Tiny Timber" in order to exchange data between robots. Tiny Timber is a very lightweight, real-time kernel for small, event-driven embedded systems. It implements reactive objects as a way of structuring embedded software. These objects are components that react to incoming events by updating their internal state and issuing an outgoing event. Implementing a control system based on reactive objects enhances the reactivity of the system and it helps to optimize the energy consumption, as the system goes to sleep mode when there is nothing to react to. The device driver for nRF24L01 radio module which you are provided with its code is developed in C language. The antenna is interfaced with an AT91SAM7S256 ARM microcontroller via Serial Peripheral Interface (SPI) produced by ATMEL . This microcontroller is mounted on SAM7P256 board which is manufactured by Olimex.

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Mohsen Amerion, M.Sc. in Computer Systems Engineering, specialized in Cooperating Embedded Systems, Studied at Halmstad University, Sweden

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