Invalid time in real time clock

Christian Weisgerber naddy at
Sun Feb 2 15:54:34 UTC 2014

Christian Weisgerber <naddy at> wrote:

> > atrtc0: WARNING: Battery failure indication
> > Invalid time in real time clock.
> > Check and reset the date immediately!
> > 
> > Incongruously, the RTC time is actually correct.  Well, off by a
> > minute or so.  Clearly the new battery is good.
> Turns out I misunderstood this.  I thought the system time was still
> set from the RTC despite the warning.  It isn't.

Still, booting into the BIOS shows that the RTC keeps up, so it
shouldn't be a battery problem.  I cleared the RTC memory, set the
date and time in the BIOS again, but I still get the warning and
FreeBSD ignores the RTC.  It looks like the RTCSD_PWR bit is stuck
and there is no way to reset it.

Christian "naddy" Weisgerber                          naddy at

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