Hi Peng, > but when I read RF230layerP I found that these two values only calculated > when there message is about to be transmitted, So it is not possible to > measure environment noise using this value. So is there some better way?
That is correct. If you want to continuously measure the RSSI noise, then you need to modifiy the code substantially. I would add a timer and do the measurements from there, but you also need to block transmissions while you are doing the RSSI measurements. It is nog going to be easy. > The other question is about the tasklet_async and Tasklet interface, I do > not understand its function, someone can explain it to me? The whole RF230 stack has 1) an interrupt handling top half contex which does almoth nothings, just schedules the next layer do do something, an 2) an interrupt handling bottom half, which does everything asynchrnously, and 3) a task context which keeps the contact with the application via commands and events. You can configure the RF230 to execute everything in layer 2) in a task context (schedule the work) or in interrupt context (do it immediately after context 1). This is what tasklets are for. The tasklet_async is a macro wihch is turned into async when 2) is run inside 1) and eliminated when 2) is run inside 3). tasklet_norace behaves similarly. Miklos _______________________________________________ Tinyos-help mailing list Tinyos-help@millennium.berkeley.edu https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
