Hi Silvan,

I think the problem is with the configuration of CC2420 on Shimmer. We
have run into this as well. Can you please two files in your
platforms/shimmer/chips/cc2420 with the ones I have attached and check
if this fixes your problem?

Miklos

On Mon, Nov 22, 2010 at 1:57 AM, Omprakash Gnawali
<[email protected]> wrote:
> ---------- Forwarded message ----------
> From: Silvan Nellen <[email protected]>
> Date: Mon, Nov 8, 2010 at 7:36 AM
> Subject: [Tinyos-help] Software auto acknowledgements break packet
> timestamps in the C2420 driver
> To: "[email protected]" 
> <[email protected]>
>
>
> Hello,
>
>
>
> I’m trying to run the FTSP test application (revision 5215 of
> http://tinyos-main.googlecode.com/svn/trunk) as described in
> tinyos-2.x/apps/tests/TestFTSP/Ftsp/README.txt on Shimmer. At first
> the nodes running TestFtspAppC didn’t seem to respond to the messages
> sent out by the beacon mote (java FtspDataLogger reported nothing).
> Using a packet sniffer I discovered that the FTSP motes send ACK
> packets for each beacon message but they don’t send report messages
> (which would then be picked up by the base station and ultimately be
> displayed by the FtspDataLogger).
>
>
>
> I looked at the CC2420 driver source code in
> tos/chips/cc2420/receive/CC2420ReceiveP.nc and used printf to see
> what’s going on, and I think I found the problem:  the outgoing ACK
> messages trigger the SFD interrupt and cause a timestamp to be put in
> to the timestamp queue (line 190). If this happens BEFORE the
> timestamp of the incoming packet is read, the packet timestamp is
> cleared and the timestamp queue gets flushed (lines 633-635).
> Consequently all packets received by the FTSP test application contain
> invalid timestamps and are thus ignored (line 67 in TestFtsp.nc).
>
>
>
> Does that make sense? Is this a known problem? Has FTSP ever been
> tested with CC2420?
>
>
>
> As a temporary fix I added PFLAGS += -DCC2420_NO_ACKNOWLEDGEMENTS to
> the Makefile and I get messages from the FTSP motes now, however this
> fix doesn’t really address the cause of the problem…
>
>
>
> Silvan
>
>
>
> _______________________________________________
> Tinyos-help mailing list
> [email protected]
> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
>

Attachment: HplCC2420InterruptsC.nc
Description: Cdf file

Attachment: HplCC2420InterruptsP.nc
Description: Cdf file

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