[time-nuts] How to get PPS from ublox mini-PCI GPS to APU2 SoC serial port for ntpd

[Paul]

[I'm responding to the list in case I need correcting]

On Tue, Aug 23, 2016 at 3:03 AM, STR . <strykar at hotmail.com> wrote:

> Old net4501's are inexpensive, they do occasionally pop up on ebay for
> around $20-40 but as making the TAPR Clock-Block is not something I can do
> I never bought a 4501.
>

 You started with NTP and my responses have all been in that context.  The
Soekris modification is an example of time-nut pursuit of a goal.  A side
effect was a very good NTP local clock.  If you goal is a very good local
clock then that's an approach.  If you goal is time transfer using NTP over
ethernet then it's over-kill.  I'm not sure of your  goal.

Modern replacements for the 4501 have been discussed previously.  E.g. the
BeagleBone Black can be clocked externally and has co-processors that can
do hi-res time stamps independent of the primary CPU.