Thanks for the reply.

One more related question.

I used the LocalTimeMicroC component in Tinyos1.x, and wired the LocalTime
interface to my application, to measure the time difference between the
sending of a packet and receiving an ACK(using GenericComm ).

I just did:

sendTime = call LocalTime.read(); // just before sending

and

receiveTime = call LocalTime.read(); // upon receiving the ack packet

and computed

timeDiff = receiveTime - sendTime

This is giving me values like: 14,857

So is this value in exact Microseconds? If it is - then I think I am getting
decent values: 14.8 ms - time to send a packet and receive its ack.

Somnath Mitra



On Wed, Jun 18, 2008 at 12:57 AM, Eric Decker <[EMAIL PROTECTED]> wrote:

>
>
> On Tue, Jun 17, 2008 at 8:35 PM, Shomnat Mitra <[EMAIL PROTECTED]> wrote:
>
>> Hello ,
>>
>> The telosb has a 32768 Hz crystal.
>>
>> So the lowest precision of time that it can measure is :
>>
>> 1/ 32768 seconds = 30.517us
>
>
> That is the underlying clock running timerB which is used to provide
> TMilli.
>
>>
>>
>> So when we use a Timer<TMicro> interface , is this precision we get ?
>
>
> TMicro is actually based on the main system clock running TimerA.  It
> clocks at 1MHz
> and the 32K timer is used to calibrate it.  This is the timing source used
> for TMicro.  You
> really do get close to 1us ticks.
>
> eric
>
>
>>
>>
>> What about LocalTime.get() 's precision ?
>>
>> Thanks in advance ,
>> Somnath Mitra
>>
>> _______________________________________________
>> Tinyos-help mailing list
>> [email protected]
>> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
>>
>
>
>
> --
> Eric B. Decker
> Senior (over 50 :-) Researcher
> Autonomous Systems Lab
> Jack Baskin School of Engineering
> UCSC
>
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