Hi, Omar: There are success stories about sampling at 4KHz. You may be able to get 8KHz. If the mote is a dedicated acoustic processing mote, perhaps you can try to use getContinuousADCData to sample at a high rate like 8KHz. This, however, may affect other components like the radio and other sensor components.
On the other hand, the common ADC.getData() has better chance to work harmoniously with other components, but less chance to sample at a high rate. In our group, we tried to sample acoustic signals at 1KHz and it works fine with other sensing, communication, and computation tasks running simultaneously. A related factor is how acurate the signal sample must be. ADC.getData, as far as I know, may have a slight jitter on the sampling time due to the timing of executing ADC.getData(). This is not a problem until you sample at a high rate. I am not sure if you can sample at 20KHz. If the processor is running at about 7MHz. Ideally you can execute 7M instructions. Divided by 20K, for each sample you have 350 instructions. This includes all the interrupt handling, hardware operation, and signal processing. You have to run signal processing because the 4K memory cannot log data for more than a fraction of a second for offline processing. And the flash write would appear to be relatively slow so it would be tricky to log data into flash. Good luck! lin On Fri, Jan 28, 2005 at 12:12:08PM -0800, Omar Tahboub wrote: > > > Can some body infrom me about the maximum sampling > rate that can be gained from a mote? > I am working on Mic Sensor project, and I am trying to > detect and sample human voice. in order to abtain an > acceptable sampleing rate, the rate should be from 8 > kHz to 20 kHz. How can I reach this sampling rate by > using a MicaZ? > > Thanks in advance, > > Omar Tahboub. > > > > __________________________________ > Do you Yahoo!? > The all-new My Yahoo! - What will yours do? > http://my.yahoo.com > _______________________________________________ > Tinyos-users mailing list > [email protected] > http://mail.Millennium.Berkeley.EDU/mailman/listinfo/tinyos-users -- Lin Gu Department of Computer Science University of Virginia Tel: 434-825-3115 Web: http://www.cs.virginia.edu/~lg6e -------------------------------------- _______________________________________________ Tinyos-users mailing list [email protected] http://mail.Millennium.Berkeley.EDU/mailman/listinfo/tinyos-users
