Those fields are common to the TOS headers I know of
but different radio chips and protocols use different
structures. The CC1000 uses just those fields but the
CC2420 adds the ones you originally asked about and
jumbles them around. See the various header files
for each platform (in T1 they were called AM.h, I
don't know about T2).

Destination ID is the "addr" field. Sequence numbers
and any other management fields are added at higher
levels. The multi-hop systems I'm familiar with add
their own "header" structures in the data area of
the message befoe the actual user payload.

I'm a little surprised that they are defined as nx_
as that reverses the byte order from the T1 versions
and I though the CC2420 actually looks at some of the
fields itself...I could be wrong about that though...

MS


João Paulo Amaro da Costa Luz Carneiro wrote:
> Thanks Michael,
> 
> What is then the basic header sent in every package? Is there a generic 
> header used by all radios for TOS2?
> Is this it (from:http://www.tinyos.net/tinyos-2.x/doc/html/tep111.html 
> cc1000_header)?
> nx_am_addr_t addr; //source?
> nx_uint8_t length;
> nx_am_group_t group;
> nx_am_id_t type;
> 
> And destination, sequence number for acks? Are added in higher level 
> protocols?
> Also can someone tell me if TOS uses a contention mechanism such as 
> RTS/CTS?
> Or  maybe better just point me out where I could read about the 
> implementation details (as other questions will probably come)?
> Thanks. Regards,
> 
> Joao
> 
> 
> On Jul 22, 2009, at 8:50 PM, Michael Schippling wrote:
> 
>> I think those are standard 802.14 header elements. the cc2420
>> 0r 802 specs might explain them. I've never seen them used for
>> anything.
>>
>> MS
>>
>> João Paulo Amaro da Costa Luz Carneiro wrote:
>>> Hi all,
>>> To explore the header of packets in tos2 I checked the CC2420.h
>>> Can someone tell me what are the fcf and destpan fields?
>>> Also, what is the dsn used for in the MAC level? Just for the acks 
>>> or  for anything else?
>>> Regards,
>>> Joao
>>> _______________________________________________
>>> Tinyos-help mailing list
>>> [email protected]
>>> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
> 
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