Lesson 02 slides for one day introductory course on wireless sensor networks and TinyOS, that took place at the University of Alcalá de Henares in Madrid Spain the 18th of September 2013. This course was jointly designed by the Electronics Department of the university and Advanticsys. Find source code for the lessons here: http://www.advanticsys.com/wiki/index.php?title=TinyOS%C2%AE_Course_at_UAH_18th_September_2013