I'm a beginner in Contiki World. I'm working with TmoteSky motes. I can read internal sensors but I had not found any information or examples about how to read ADC ports (pin expansions) in order to use external sensors. (Light, Temperature and Humidity).
I cannot find any information about that.
You should look around this link where you can find some examples, especially the second which discusses reading temperature periodically.
Hope it could help you.