[Tinyos-devel] FTSP testing result

[Omprakash Gnawali]

On Tue, Feb 3, 2009 at 2:16 PM, Branislav Kusy <kusy at stanford.edu> wrote:
>> The current version of FTSP has a quantization bug in it while
>> calculating the sum of squares. Therefore, the time synchronization
>> error is always around +/- 4ms. I attached a patch to this email which
>> fixes this. Not sure if this helps with your problems though.
>
> it's interesting this bug didn't come up earlier. i guess because everybody
> used TMicro, or T32khz before - so it wasn't a big deal as the quantization
> error was on par with the timestamping error. nice catch!
>
> i think the problems are in timestamping. i modified cc2420 radio stack to
> fix some timestamping bugs last year, but it seams it didn't propagate to
> the CVS head. should i just go ahead and commmit it? owners of the stack
> should take a look. only two files were modified:
> http://tinyos.cvs.sourceforge.net/viewvc/*checkout*/tinyos/tinyos-2.x-contrib/stanford-lgl/apps/tests/TestPacketTimeStamp/CC2420ReceiveP.nc?revision=1.2
> http://tinyos.cvs.sourceforge.net/viewvc/*checkout*/tinyos/tinyos-2.x-contrib/stanford-lgl/apps/tests/TestPacketTimeStamp/CC2420TransmitP.nc?revision=1.2
>

I had assumed those fixes were already in the stack. Let me know when
you patch in Thomas's fix so I can test.

- om_p