Re: GPS Mac OS challenges

[Gary E. Miller]

Yo Marc!

On Mon, 6 Dec 2021 10:42:05 -0600
Marc Rosen <marc.rosen@mac.com> wrote:

> I'm most of the way done connecting my GPS to my MBP OS X Monterrey ,
> that's to persistence and some help from Gary Miller

Should be nothing ahrd about that.

> In the end I'm using homebrew (package) versions of ntp and gpsd.

What versions?


> The
> GPS is from an Icom IC-705 radio.


That's a new one.  I assume it sends standard NMEA?

> The main difficulties were setting
> the correct serial/usb device for the GPS to connect to ,

I'm not sure that is hard.  Just put the device path on the
gpsd command line.

> increasing
> the shared memory,

I'm not sure why you would need that.

> and dealing with Mac env restrictions 

I'm not sure why you would need that.

> I still can't get ntpshmemmon to run properly- permission denied to
> connect to SHM1&2 Everything is running from sudo/root

I've never had that problem on a mac.  Maybe some new Apple specific
hardening.

> Any solutions?

Can it work?  Yes.  Do I understand your problem?  No.

> cgps shows great data

Good.

> ntpq -p shows the GPS data updating ( no PPS)

You are skipping a lot of dettails.  Please rung gpsdebuginfo and
send the output here.

In general, if ntpshmmon is not working, you can stop right that and
not look at anything else NTP.

> One question is how to test it properly 

Run gpsdebuginfo, and send the result herre.  Also try the
Toubleshooting Guide:

    https://gpsd.io/troubleshooting.html

> I want the Mac system clock to rely on the gps 

No, you want it to rely on ntpd, which may rely on GPS for part if
its data.

> I tried setting the date time system prefs to use 127.0.0.1 ,

No, you want ntpd to control your system time, not macOS.

> the
> turning off WiFi and resetting the clock manually then restore to
> automatically w 127.0.0.1 - not sure this is working right

If that is what you are doing, that is wrong.

> Any suggestions for testing?

See above.

> Does anyone know if PPS is supported by the Radio?

Probably not, but the output of "-ND 4" that I already asked for
would tell you.

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

            Veritas liberabit vos. -- Quid est veritas?
    "If you can't measure it, you can't improve it." - Lord Kelvin

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