[time-nuts] GPS Week 1536 causing problems?
Magnus Danielson
magnus at rubidium.dyndns.org
Tue Jul 7 03:13:19 UTC 2009
Hal Murray wrote:
>>>> Anyone else lose an 18x?
>
>>> I lost one a while ago. Similar. It just stopped doing anything
>>> useful.
>
>> Battery failure?
>
> I don't think it has a battery inside. That seems like a poor design. Too
> many reasonable use cases would include sitting in a drawer for extended
> periods of time.
Providing an RTC has benefits, especially when considering week-rollover
issues, since when the receiver wakes up it has no idea of date at all,
pulling in the RTC time and date is a sufficient hint, and adjusting
with detailed info from the GPS is a trivial extention. Then adjusting
the RTC is not a hard thing to do every once in a while. The same
problem could also be solved using EEPROM space. A byte would suffice.
Many of the GPS OEM boards I have seen has support for RTC battery. Is
also used to keep CMOS for waypoints.
Cheers,
Magnus
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