Re: RTC on MPC860 after complete power failure

Thanks guys for your input.

I think we've had that problem with the onboard sram (dpram or dual
port ram) being unstable during power down.

In any case, I'm hoping to find some registers with a predictable
state.

At the moment, the only one from the timers I've found is the rtcsc,
"RTC Status and Control". As far as I can tell the RTE (Real Time clock
Enable) bit is cleared on loss of KAPWR, but preserved across POR
reset. The MPC860 manual appears indicates that this field is not
cleared on reset, but none of the reset comments in the manual appear
to refer to loss of KAPWR, but instead to POR or HRESET.

Can anyone confirm that RTE is reliably cleared when KAPWR is lost?

Thanks,

Andy

PS, Paul, I don't know if you meant to post something. It looks like
your post is just a copy of previous posts :).

.

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