Hi,

I add PacketAcknowledgements for unicast packets in the demo
application<http://code.google.com/p/tinyos-main/source/browse/trunk/apps/tests/rfxlink/TestPacketTimeSync/?r=5544>
and
wire it to ActiveMessageC. The application crashes if it is using the *
cc2420x* stack. However, it works fine if the default *cc2420* stack is
used. Can you help me understand what may be going wrong here?

Ultimately, I want to make packet-level time sync work with CTP to measure
the time it takes for a packet to traverse each link. This is done by first
timestamping a packet at the sender and then piggybacking the timestamp in
the packet to the receiver. There are two options:
1) use cc2420x stack: it's necessary to get all functionality of CTP,
i.e., PacketAcknowledgements
and LinkPacketMetadata and possibly others, to work.under the new stack
2) use default cc2420 stack: fix its timestamping (both packet timestamping
and packet-level time sync) by porting the timestamping from cc2420x to
cc2420

If you have any suggestion on which venue to go and how to implement it,
please let me know. Thanks, again.

On Sun, Jul 17, 2011 at 4:25 PM, Janos Sallai <[email protected]>wrote:

> Hi,
>
> PacketAcknowledgements  is provided by ActiveMessageC. No component
> provides LinkPacketMetadata in the cc2420x (rfxlink) stack. It's not
> particularly complicated to implement that functionality, though.
>
> Janos
>
> On Sun, Jul 17, 2011 at 10:19 AM, Xiaohui Liu <[email protected]> wrote:
> > Hi,
> > Which components provide PacketAcknowledgements and LinkPacketMetadata
> > interface in cc2420x stack? If I use AMSenderC and CC2420ActiveMessageC
> as
> > in CTP, it does now compile as stated in the previous email.
> >
> > On Sat, Jul 16, 2011 at 11:22 PM, Xiaohui Liu <[email protected]> wrote:
> >>
> >> Thanks.
> >> What about packet-level time sync as stated in TEP133? Is there any
> known
> >> issue of such time sync in the default cc2420 stack? I'm using it with
> CTP,
> >> but sometimes it seems even TimeSyncPacket.isValid() returns true, the
> >> timestamp seems to be invalid (this is detected by measurements such as
> time
> >> interval close to 2 ^ 32 ms). Because packet-level time sync is based on
> >> packet timestamping, so it should have issues as well, am I right?
> >> The reason why I don't use cc2420x stack with CTP yet is that it
> >> constantly prompts compilation error:
> >> $/tinyos-2.1.x/tos/chips/cc2420/CC2420TimeSyncMessage.h:46: redefinition
> >> of `nx_struct timesync_footer_t'
> >> $/tinyos-2.1.x/tos/chips/cc2420/CC2420TimeSyncMessage.h:46: warning: tag
> >> timesync_footer_t shadows enclosing struct/union/enum
> >> $/tinyos-2.1.x/tos/chips/cc2420/CC2420TimeSyncMessage.h:49: conflicting
> >> types for `timesync_footer_t'
> >> $/tinyos-2.1.x/tos/lib/rfxlink/layers/TimeSyncMessageLayer.h:58:
> previous
> >> declaration of `timesync_footer_t'
> >> What changes are necessary to use packet-level time sync compatibly with
> >> CTP? Thanks very much.
> >> On Thu, Jun 16, 2011 at 2:53 PM, Janos Sallai <
> [email protected]>
> >> wrote:
> >>>
> >>> Timestamping has known issues in the default cc2420 stack (telosb,
> >>> micaz, etc.) under heavy load. Try using the cc2420x stack. Compile
> >>> with "make telosb cc2420x". You'll need the latest sources from google
> >>> code.
> >>>
> >>> Janos
> >>>
> >>> On Thu, Jun 16, 2011 at 1:34 PM, Xiaohui Liu <[email protected]> wrote:
> >>> > I'm using the default one, I'm not sure how to use cc2420x.
> >>> >
> >>> > On Thu, Jun 16, 2011 at 1:50 PM, Janos Sallai
> >>> > <[email protected]>
> >>> > wrote:
> >>> >>
> >>> >> Is this the default cc2420 stack, or do you use cc2420x?
> >>> >>
> >>> >> Janos
> >>> >>
> >>> >> On Thu, Jun 16, 2011 at 10:49 AM, Xiaohui Liu <[email protected]>
> >>> >> wrote:
> >>> >> > Can anyone please give me some hint on what may be the cause? I'm
> >>> >> > stuck
> >>> >> > here. I really appreciate your assistance.
> >>> >> >
> >>> >> > On Wed, Jun 15, 2011 at 4:57 PM, Xiaohui Liu <[email protected]>
> >>> >> > wrote:
> >>> >> >>
> >>> >> >> Telosb.
> >>> >> >>
> >>> >> >> On Wed, Jun 15, 2011 at 4:54 PM, Hamid Rafiei
> >>> >> >> <[email protected]>
> >>> >> >> wrote:
> >>> >> >>>
> >>> >> >>> Hi,
> >>> >> >>>
> >>> >> >>> What is the platform you are using?
> >>> >> >>>
> >>> >> >>>
> >>> >> >>>
> >>> >> >>>
> >>> >> >>>
> >>> >> >>> Regards,
> >>> >> >>>
> >>> >> >>>
> >>> >> >>> Hamid Rafiei Karkvandi
> >>> >> >>>
> >>> >> >>>
> >>> >> >>>
> >>> >> >>>
> >>> >> >>>
> >>> >> >>> On Wed, Jun 15, 2011 at 2:36 PM, Xiaohui Liu <[email protected]>
> >>> >> >>> wrote:
> >>> >> >>>>
> >>> >> >>>> Hi everyone,
> >>> >> >>>>
> >>> >> >>>> I'm using PacketTimeStamp interface to timestamp packet
> >>> >> >>>> transmission
> >>> >> >>>> and
> >>> >> >>>> reception, but I find isValid() returns FALSE more than 90% of
> >>> >> >>>> the
> >>> >> >>>> time. Can
> >>> >> >>>> anyone help me understand what may go wrong? I'm timestamping
> in
> >>> >> >>>> sendDone()
> >>> >> >>>> and receive() event only and sending 1 packet per second. Any
> >>> >> >>>> help is
> >>> >> >>>> appreciated.
> >>> >> >>>> --
> >>> >> >>>> -Xiaohui Liu
> >>> >> >>>>
> >>> >> >>>> _______________________________________________
> >>> >> >>>> Tinyos-help mailing list
> >>> >> >>>> [email protected]
> >>> >> >>>>
> >>> >> >>>>
> >>> >> >>>>
> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
> >>> >> >>>
> >>> >> >>
> >>> >> >>
> >>> >> >>
> >>> >> >> --
> >>> >> >> -Xiaohui Liu
> >>> >> >
> >>> >> >
> >>> >> >
> >>> >> > --
> >>> >> > -Xiaohui Liu
> >>> >> >
> >>> >> > _______________________________________________
> >>> >> > Tinyos-help mailing list
> >>> >> > [email protected]
> >>> >> >
> >>> >> >
> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
> >>> >> >
> >>> >
> >>> >
> >>> >
> >>> > --
> >>> > -Xiaohui Liu
> >>> >
> >>
> >>
> >>
> >> --
> >> -Xiaohui Liu
> >
> >
> >
> > --
> > -Xiaohui Liu
> >
>



-- 
-Xiaohui Liu
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