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

[Singh, Daljeet]

Hi Gary,

 

“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.   

 

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

 

“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.

 

Thanks- Daljeet

 

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

?WATCH={"enable":true,"json":true}\

{"class":"DEVICES","devices":[{"class":"DEVICE","path":"/dev/ttyPS1","driver":"NMEA0183"

 

{"class":"VERSION","release":"3.23.1","rev":"3.23.1","proto_major":3,"proto_minor":14}

?WATCH={"enable":true,"json":true}

{"class":"DEVICES","devices":[{"class":"DEVICE","path":"/dev/ttyPS1","driver":"MTK-3301","subtype":"AXN_3.10_3333_12112701-3316-MC-GG-"

 

 

timespec_t gpsd_gpstime_resolv(struct gps_device_t *session,

                               unsigned week, timespec_t tow)

{

    timespec_t t;

 

    if (week < 1024)

        week += session->context->rollovers * 1024;

 

    session->context->gps_week = week;

    session->context->gps_tow = tow;

    session->context->valid |= GPS_TIME_VALID;

 

    return t;

}

 

-----Original Message-----
From: gpsd-users-bounces+daljeet.singh=spx.com@nongnu.org <gpsd-users-bounces+daljeet.singh=spx.com@nongnu.org> On Behalf Of Gary E. Miller
Sent: Thursday, November 10, 2022 12:43 PM
To: gpsd-users@nongnu.org
Subject: Re: 1024 Week Rollover issue with MT-3333 based GPS Receiver

 

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