[Tinyos-devel] packet timestamping and packet-level time synchronization

[Michael Newman]

The interfaces being designed are targeted at measuring time based on when
interrupts occur.

I think it would be a good idea to think about an interface that could
handle more accurate hardware measures.

A hardware based system would start or capture a timer when the radio's
reference line was raised (lowered) to indicate the arrival of a particular
symbol within a message (SFD in the CC2420). When the interrupt arrives the
timer controlled by the radio pin and the timer that keeps the current clock
are inspected and the clock time the message arrived computed. Assuming the
clock timer is fast enough and precise enough this technique can give times
that are accurate to about 1/2 of a symbol time.

-----Original Message-----
From: tinyos-devel-bounces at millennium.berkeley.edu
[mailto:tinyos-devel-bounces at millennium.berkeley.edu] On Behalf Of Janos
Sallai
Sent: Monday, May 12, 2008 4:52 PM
To: TinyOS Development
Subject: [Tinyos-devel] packet timestamping and packet-level time
synchronization

I am attaching two TEP drafts, one on packet timestamping, the other one on
packet-level time synchronization. Comments are welcome.

Thanks,

Janos Sallai