[time-nuts] tyco electronics A1025
francesco.messineo at gmail.com
Sun Dec 14 12:29:16 EST 2014
On Sun, Dec 14, 2014 at 6:12 PM, Bob Camp <kb8tq at n1k.org> wrote:
>>> It’s unlikely that a consumer targeted GPS has a good dedicated PPS out of it. Finding one that will do position hold is even less likely. You can get modules that will do both for < $20 and have a documented interface.
>> that's not meant as a "time nut" stratum 1.
>> It's just a free gps module I would like to recycle as a needed
>> stratum 1 server for a small network.
>> Of course if I can find informations on it.
>> I know there're better options, but in this case anything would do.
> … and NTP is not a GPSDO or a Cs replacement.
> My guess is that there is no PPS out of the device. It would be very unusual if there was. Finding the NEMA output pin should be possible with an oscilloscope. At that point, a simple serial connection to the server is about all you need. Bring up the NEMA driver and it is running. It is unlikely that any further optimization would be possible, even with the (maybe) 290 page data sheet on the part. I would not let the lack of a data sheet stop you in this case. Hook up the output to a PC with a terminal program and see what you get. The main problem would be if you need to find the serial input pin to change what it puts out, hopefully you do not.
The A1029, which is a newer model, has indeed a PPS output and I've
been able to find a datasheet for it but the pinout isn't anything
like the A1025.
I planned to reverse engineer the pinout, but I'd like at least not to
be forced to try to guess the power pins. Maybe someone still has the
data for this older module.
More information about the time-nuts