On Nov 3, 2008, at 1:25 PM, Michael Schippling wrote: > Lets put this on the help list to keep a record.... > > The Intelligent Designers kind of arbitrarily limited the > Timer driven sampling to a 3ms period on micas, although using > Timer2<TMilli> on the tmotes I have used 2ms (presumably even > 1ms works...). If you want to get to .5ms you'll have to look > into the HighFrequencySampling example or dig into the > aforementioned "ADC prescalar" and free-running the converter.
It's not arbitrary. It's because the underlying clock is running at 1MHz, and the way the timer interrupts work in the atmega128 you can't ask for something in 1-2 clock ticks and expect to reliably get an interrupt. There was a big discussion on this on -devel back in 2004. Here's a link to the threads: https://www.millennium.berkeley.edu/pipermail/tinyos-devel/2004-August/thread.html Phil _______________________________________________ Tinyos-help mailing list [email protected] https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
