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GPS Date Roll Over problem
#1
Bug 
One bit missing in the GPS week counter implies GPS week number falls to zero after 1023 weeks ! Consquently the date indicated becomes unusable !
Not only the date is affected (infested ?) but the position also can be impacted. a COLD START will bring back the correct  position, but the date will permanently remain affected.
Furuno writes for its GP 32 / 37 : No software solution planed to solve the problem !
See Furuno note attached to this thread.
If this is not programmed obsolescence what is it ?

Same date issue occured with Ublox GPS Mouse USB modules (Ublox 6, 7 & 8 chips). Ublox issued a note (attached here below), saying :
Code:
The most robust workaround for the GPS week number roll-over issue is to add a compensation
algorithm to the customer application running on the host processor. The algorithm accepts the
wrong date from the receiver, and then translates that to the correct date before passing it further in
the application stack.

Is it possible to implement such compensation in signal K ? The value of the compensation should be adjustable to cope with different firmware implementations ...

PS ; Dear Moderators please feel free to move this thread to the bug section !


Attached Files
.pdf   GPS-WeekNumber-Rollover-Workaround_AppNote_(UBX-19016936)(2).pdf (Size: 218.22 KB / Downloads: 797)
.pdf   u-blox-GPS-WeekNumberRolloverWorkaround_IN_(UBX-19039990).pdf (Size: 78.81 KB / Downloads: 332)
Cordialement
Didier B
Pi4, SSD USB3, OP 3.0 Touch SK 3.2.1 OpenCPN  5.8.4 :  Thank you  Thank you  Thank you


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#2
I’ve seen this issue with GPS too.
Returns correct time but wrong date.
If this problem doesn’t exist in
GLONASS, Beidou, Galileo
might be solution would be
never trust gps date and use date from
from one of those in SignalK set date time plugin?

Thanks
Download BBN Marine OS for raspberry pi 

https://bareboat-necessities.github.io/m...at-os.html

Video of actual installation:

https://www.youtube.com/watch?v=3zMjUs2X3qU


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#3
Please: if you want something to change in Signal K and the attention of the developers I urge you to create issues in Signal K Github, like Mikhail did for this one: https://github.com/SignalK/signalk-server/issues/1335
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#4
(2021-08-07, 12:09 PM)tkurki Wrote: Please: if you want something to change in Signal K and the attention of the developers I urge you to create issues in Signal K Github, like Mikhail did for this one: https://github.com/SignalK/signalk-server/issues/1335
Hello tkurki and thanks for your reply !
Also thanks to mgrouch who already did the job by posting the point to Signal K Github !
Glad to find it in the list of issues !
Cordialement
Didier B
Pi4, SSD USB3, OP 3.0 Touch SK 3.2.1 OpenCPN  5.8.4 :  Thank you  Thank you  Thank you


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