[ntp:questions] Fwd: Re: NetBSD GPS/PPS using 4.2.6p3
uwe at klein-habertwedt.de
Fri Aug 26 07:41:02 UTC 2011
A C wrote:
>> I will try to capture the outgoing serial data sometime either this
>> weekend or the next when I have a bit more time. I'll send it along to
>> the list as soon as I do. For now I'll leave things using PPS only and
>> see how it works. But I still want to eventually get the GPS refclock
>> working along with PPS just to have a backup clock for network outages.
> Ok, so I've spliced up a serial tap cable to snoop on the data heading
> out towards the GPS. Unfortunately I can't seem to decode it. No
> amount of changing baud rates, stop bits and parity seems to show me
> anything but a stream of unreadable binary data.
> It seems to be coming out at 4800 baud although stty says the output
> speed of the port is 9600. The data seems to have a regular pattern to
> it with a few of the bytes changing.
> If anyone can think of a utility that will attempt to autosync to the
> data I'm open to suggestions. Otherwise I can try to capture the raw
> data if anyone wants to look at it. Either way, it only transmits while
> ntpd is using the port. If ntpd is shut down the data stops.
Can you access the output strings via a debugger?
i.e. trace writes on the port for that process?
Much easier to get an idea what is actually sent.
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