Re: DS3231 RTC module not detected

From: Archimedes Gaviola <archimedes.gaviola_at_gmail.com>
Date: Sun, 20 Feb 2022 04:29:06 UTC
On Sun, Feb 20, 2022 at 11:51 AM Daniel O'Connor <darius@dons.net.au> wrote:

>
>
> > On 19 Feb 2022, at 22:49, Archimedes Gaviola <
> archimedes.gaviola@gmail.com> wrote:
> > Thanks for your feedback Daniel! With the exact DS3231 driver all the
> concerns I've mentioned were answered. Once it is set manually via date or
> ntpdate, the clock will now continue even if your system is shutdown (with
> unplug power cable) or even detaching the module from the RPi4 system for
> some time and then attaching it back will now be "real-time".
> >
> > You can bring your DS1307 with the exact driver as well. Thanks a lot
> for your help, it is well appreciated.
> >
> When you say "with the exact DS3231 driver.." what do you mean?
>

I mean the appropriate DS3231 driver - ds3231(4) for the module which is a
kernel loadable as the dominating driver with 13.0-RELEASE and 14.0-CURRENT
which is MAX77620 RTC is the wrong one thus the module will not work
properly. The clock stops and goes back to the time when you set it. This
behavior is observable when my RPi system is rebooted or shutdown. With the
loadable  ds3231 driver, this behavior is no longer observed and working as
expected. For your DS1307, there's also an equivalent and perhaps the
appropriate driver as described in the manual ds1307(4), it can be loaded
as well via kldload.

Thanks,
Archimedes