Queue and time sync
Muhammad Azhar <leo_az_83 <at> hotmail.com>
2007-03-01 09:25:21 GMT
If a number of motes are sending data to the root every 10 secs, does the
root need some sort of Queue to enqueue the messages, so that no messages
are lost? 'Coz when I did something like this, there were a few instances
when the motes were not sending messages to the root, although it'd come
back later. The motes were places statically, so is it possible that the
link quality is affecting the transmission? Or is it simply because I
didn't put my messages in queue, thus, some messages were not processed by
Also, are there any recommended articles on simple time synchronization?
I've read RBS and TPSN, but I don't really know how to implement the former
while for the latter, I do not have any idea on lowering the granularity of
the clock as well as time stamping the packets at the RFM layer instead of
the application layer. Although there are codes for the latter, I think
they're really quite complex. I'd like to implement a really simple time
By the way, what exactly does "local clock" mean? Is it just referring
to the timer value? In that case, wouldn't all "local clocks" start from
zero? If it is referring to a specific time, then how do we implement this?
In fact, is it possible to do this if my root is permanently attached to
the USB port of the PC where it is always receiving data? Also, if we want
to use a reference clock, does it mean that other motes do not necessarily
need a "clock"?
I'm really quite lost on implementing time sync. Furthermore, I can't
seem to find pseudocodes on this too (the only codes I found were
implemented by Saurabh G. which I really find too complex). But most
importantly, I need to know what local clock is referring to. Many thanks
for your patience.