On Oct 11, 2008, at 3:29 PM, elliot chen wrote: > Hi All, > > We are a company focused on WSN products development in China. We > have developed a product based on TinyOS 2.X, now we are having a > problem related to the power management. Here is a brief description > of the problem. Hopefully we can get some help from you. > > 1. According to the document, TinyOS will go into sleep state when > there is no task in the task queue. As we are using MP430 MPU, even > in the LPM0 mode, it should be 75uA, but what we found out is about > 200uA. > 2. We found that in the sleep state, TinyOS still wakeup at every 2 > second and do some operating system related maintenance. We don't > know whether the power was used by these maintenances. > 3. Can we enlarge the 2 seconds interval to save more energy? > 4. Can we simplify the maintenance tasks? > 5. What is the preferred approach for the power management? We need > to reach 20uA level to get the required battery life.
The 2 seconds is because it's waking up on a 16-bit overflow of a 32kHz clock. This wakeup cost, however, should be tiny. It sounds like your software has left a peripheral on, such that it's drawing power. One easy way to figure out where the power is going is to hook up a multimeter. Phil _______________________________________________ Tinyos-help mailing list [email protected] https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
