[Tinyos-help] Precise contents and length of the 802.15.4 frames (and most especially with the TestNetwork App)

[roberto pagliari]

the type is the identifier of the stream, like -> GenericComm.SendMsg
["type"];

On 7/5/07, roberto pagliari <bobtinyos07 at gmail.com> wrote:
>
> I think the module CC2420RadioM send a payload (excluding headers and
> footers) of TOSH_DATA_LENGTH, regardless of the particular size of your
> message. the only way is to change the TOSH_DATA_LENGTH definition within
> ..\micaz\AM.h
>
>       pMsg->fcflo = CC2420_DEF_FCF_LO;
>       if (bAckEnable)
>         pMsg->fcfhi = CC2420_DEF_FCF_HI_ACK;
>       else
>         pMsg->fcfhi = CC2420_DEF_FCF_HI;
>       // destination PAN is broadcast
>       pMsg->destpan = TOS_BCAST_ADDR;
>       // adjust the destination address to be in the right byte order
>       pMsg->addr = toLSB16(pMsg->addr);
>       // adjust the data length to now include the full packet length
>       pMsg->length = pMsg->length + MSG_HEADER_SIZE + MSG_FOOTER_SIZE;
>       // keep the DSN increasing for ACK recognition
>       pMsg->dsn = ++currentDSN;
>       // FCS bytes generated by CC2420
>       txlength = pMsg->length - MSG_FOOTER_SIZE;
>       txbufptr = pMsg;
>
> txbufptr is the pointer to the TOS_Msg to be transmitted, but within
> TOS_Msg a uint8_t buffer of TOSH_DATA_LENGTH size is defined.
>
> On 7/3/07, Philip Levis <pal at cs.stanford.edu> wrote:
> >
> > On Jul 3, 2007, at 2:10 PM, John Griessen wrote:
> >
> > > Steve McKown wrote:
> > >> 3 - If it's not.. what use does it have?
> > >>
> > >
> > > The metadata is useful for writing network functionality.  It's
> > > used in CTP for example, to manage neighbors and routing.  I don't
> > > think you'd want an application to use metadata directly, since
> > > you're then tying that application to a specific bit of radio
> > > hardware.
> > >
> > >
> > > So timestamp metadata should go in a component or an interface?
> > >
> > > Has anyone found the most accurate way to deterministically
> > > clock the arrival of a timing packet, that can be recognized
> > > without decoding,
> > > since its data content never varies?   (The application I have in
> > > mind is precise timestamping.)   Is there any physical output of
> > > the radio for the
> > > timing of a received packet as the radio locks onto its data
> > > transitions, or
> > > is packet timing and recognizing  all internal and a RX ready
> > > interrupt is the earliest
> > > output?
> >
> > Take a look at the RadioTimeStamping interface. Some radio stacks
> > issue an event on the first data bit of a packet, right after the
> > preamble.
> >
> > Phil
> > _______________________________________________
> > Tinyos-help mailing list
> > Tinyos-help at Millennium.Berkeley.EDU
> > https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
> >
> >
>
>
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