Do anybody has idea or maybe explain to me what is the embedded os doing? As what I did until now, I'm just playing with the 16bit microcontrollers. (PICs and AVRs). I saw that in the 'bigger' microcontroller like ARM7 based with a lot of enhancements, they use an operating system. What does it do and why in the small microcontroller, there are no operating system?
GO to MENTOR site embedded section and register to download several power point presentation & lecture (PDF) who will tell you a lot about operating system and how they works