Re: 1024 Week Rollover issue with MT-3333 based GPS Receiver

[Gary E. Miller]

Yo Daljeet!

On Fri, 11 Nov 2022 01:18:41 +0000
"Singh, Daljeet" <Daljeet.Singh@spx.com> wrote:

> "There have been a number of changes here and there to support 1024
> week rollover bugs.  Finding them all will take a lot of work.  Just
> be happy it works."
> 
> 
> 
> I am thankful but when I don't know why something is doing what it is
> doing, it does not make me feel good.  I have a feeling that the code
> below does the trick even though it should not.

Feel free to go through gobs of commits to find the relevant ones, but I
do not have time for that.

Most people trust in the regression tests.  When the regression tests
pass the code is working.  And that keeps it from staying broken for
long.

> I also notice that the driver used by the older gpsd version 3.15 is
> different than that used by 3.23 for the same GPS module and this
> might be altering the date behavior too.

3.15 is unsupported, I'll not comment on it.

> Looks like MTK-3301 driver
> has more smarts than the generic  NMEA0183 driver as may be expected.

Does not metter, they are not compatible, so gpsd picks the one for the
current jon.  Automagically.

> "You should upgrade your MT333 F/W as well." => My idiotic vendor
> says that the F/W can't be upgraded. Can you believe that.

Sadly, yes.  Best to just junk them and get a modern GNSS receiver.

> {"class":"VERSION","release":"3.15","rev":"3.15","proto_major":3,"proto_minor":11}

I'm not sure what that is about, or why you sent it.  In any case, 3.15 is so
old, we don't support it anymore.

> timespec_t gpsd_gpstime_resolv(struct gps_device_t *session,
>                                unsigned week, timespec_t tow)
> {

I'm not sure why you sent that, and without saying where it is from, not
useful.  Since it is not from the current gpsd version, unsupported.

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

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