Testing ntpd and/or timing from gpsd

[Gary E. Miller]

Yo Hal!

On Tue, 10 May 2016 15:58:30 -0700
Hal Murray <hmurray at megapathdsl.net> wrote:

> Real serial ports on a PC include that sort of chip.  Nobody worries
> about the delay through it.

The delay is fixed.  You could look on the data sheet, find the
propogation time, and fudge it out.  

Here is the MAX232 data sheet:

http://www.ti.com/lit/ds/symlink/max232.pdf

The prop delay is 500 nanoSec.  Almost, but not quite, in the noise floor
of the best time servers..

If you have a PTP server you can compare that to your PPS, and just add
a fudge to remmove it.

If that 500 nanoSec realy matters to you, then no software solution is
right solution.

RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
	gem at rellim.com  Tel:+1 541 382 8588
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