RTC on MPC860 after complete power failure

Does anyone know if the RTC on an MPC860 can be relied upon to have any
particular value or range of values following complete loss of power
(that is, including loss of KAPWR power)?

Unfortuneatly our reset button asserts POR and HRESET, so the RSR can't
differentiate between the reset button and actual power loss. We are
hoping the RTC defaults to a predictable state when KAPWR and all other
power is lost.

If the RTC isn't predictable, does anyone know of any other register
that is, that can be used to detect actual loss of all power?

A quick test of 11 power fails showed our RTC with the values:
7FFFFFFF once
75F5FDFF twice
75F57DFF three times

.

Quantcast