Scheduler Delayed // Openhab 3.0.2 and 3.1.0M5

To be precise, it is still a software issue. The pi has no hardware clock :joy:.

Anyway, thanks for your help, rossko57!

The Pi lacks a hardware real time clock to keep independent track of time of day. It has of course a hardware oscillator or clock to drive the chips, and system software can derive timekeeping from that. On Pi3/4 the chip clock is variable to control temperature (and add confusion) but its crystal regulated which should give around 100ppm accuracy. I believe the crystal works as a reference, to trim the master oscillator. Broke crystal, master oscillator runs significantly off-spec.

Thanks for the details, I am not that deep in building PC clocks. I will organize another Pi today and give an update today or tomorrow.

I am running out of ideas: I used another Pi with the same SD card and have exactly the same drift. It seems to be some kind of configuration but have no clue what. :cry:

Don’t rule out the potential of the card itself … weird stuff happens at low level storage access.

Try an openhabian setup for a standard environment.

I now have something different in mind. I still have an old line in my boot config that reduced the CPU speed dynamically:


I think that is not supported since a while anymore and somehow I don’t have a good feeling with it. Trying now…

I think the real thing runs at 250 or 500. Clock time is derived from this, in complicated fashion, so yes a source of timekeeping error.

Jupp, that’s the error. Now it works. Long process but solved. :ok_hand:

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