[Tinyos-help] atmega128 clock frequency

[roberto pagliari]

Dear Giri and Michael,

looking at the datasheet the firs 4 bits of low fuse byte are CKSEL, while
bits 4 and 5 are SUT select. Now, my fuse low byte, default by tinyos 1.0.7,
is 0xFF. Does this correspond to 8Mhz or 7.3728?

I'm asking you this because I'm getting some time interval measures, and I
need to know exactly the frequency of the microcontroller.

Thank you a lot in advance

On 7/18/07, roberto pagliari <bobtinyos07 at gmail.com> wrote:
>
> Hi Michael,
>
> I get the following configuration
>
> fuse low byte  0xff
> fuse high byte 0xff
> fuse extended byte 0xff
> calibration byte      0xff - read only
> lock bits  0xff
>
> BLB12 -> 1
> BLB11 -> 1
> BLB02 -> 1
> BLB01 -> 1
> LB2     -> 1
> LB1     -> 1
>
> simply issuing the command >>uisp -dprog=data -dpart=ATmega128 --rd_fuses
>
> what did you mean by that?
>
> On 7/17/07, Michael Schippling <schip at santafe.edu> wrote:
> >
> > whew...now I don't have to go look up the config bytes...
> > Is there an internal osc that will run faster than the xtal?
> >
> > And are we certain that the config is really all 0xff?
> > That sounds too conveniently like a read error...
> >
> > MS
> >
> >
> > Giri Baleri wrote:
> > > The low byte value of 0xff indicates that the ATmega128 is configured
> > to
> > > use external oscillator. The frequency of the external oscillator is
> > > normally 7.3728 MHz.
> > >
> > > Giri
> > >
> > >
> > ------------------------------------------------------------------------
> > > *From:* tinyos-help-bounces at Millennium.Berkeley.EDU
> > > [mailto:tinyos-help-bounces at Millennium.Berkeley.EDU] *On Behalf Of
> > > *roberto pagliari
> > > *Sent:* Tuesday, July 17, 2007 3:27 PM
> > > *To:* schip at santafe.edu
> > > *Cc:* tinyos-help at Millennium.Berkeley.EDU
> > > *Subject:* Re: [Tinyos-help] atmega128 clock frequency
> > >
> > > my actual configuration, running
> > > uisp -dprog=data -dpart=ATmega128 --rd_fuses
> > >
> > > gives me the following
> > > fuse low byte  0xff
> > > fuse high byte 0xff
> > > fuse extended byte 0xff
> > > calibration byte      0xff - read only
> > > lock bits  0xff
> > >
> > > BLB12 -> 1
> > > BLB11 -> 1
> > > BLB02 -> 1
> > > BLB01 -> 1
> > > LB2     -> 1
> > > LB1     -> 1
> > >
> > > so, is it 7.3Mhz?
> > >
> > > On 7/17/07, *roberto pagliari* <bobtinyos07 at gmail.com
> > > <mailto:bobtinyos07 at gmail.com >> wrote:
> > >
> > >     my fuse low byte is set to 0xff. this means the clock frequency is
> > >     7.3Mhz (not 8Mhz) right?
> > >
> > >     thank you in advance
> > >
> > >
> > >     On 7/17/07, *Michael Schippling* < schip at santafe.edu
> > >     <mailto:schip at santafe.edu>> wrote:
> > >
> > >         I think "change the crystal" is the only answer for the
> > ATMEGA.
> > >         It's sounds like the MSP can be overclocked in software
> > though.
> > >         MS
> > >
> > >         roberto pagliari wrote:
> > >         >  how can I set the clock frequency of motes microcontroller?
> >
> > >         >  I'm using micaz mote right now
> > >         >
> > >         >
> > >         >
> > >
> > ------------------------------------------------------------------------
> > >         >
> > >         >  _______________________________________________
> > >         >  Tinyos-help mailing list
> > >         >  Tinyos-help at Millennium.Berkeley.EDU
> > >         <mailto:Tinyos-help at Millennium.Berkeley.EDU>
> > >         >
> > >
> > https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
> > >         <https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
> > >
> > >
> > >
> > >
> > >
> > >
> > ------------------------------------------------------------------------
> > >
> > > _______________________________________________
> > > Tinyos-help mailing list
> > > Tinyos-help at Millennium.Berkeley.EDU
> > > https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
> >
> >
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mail.millennium.berkeley.edu/pipermail/tinyos-help/attachments/20070718/2f300281/attachment.htm