Re: Handling power failure - MPC5200

In message <007d01c4c37e$17e8e0d0$0301a8c0@chuck2> you wrote:

So maybe, are you thinking that a power fail interrupt is a waste of
time?  Just segment the file system as you suggested and trust the
writeable part to jffs2?

A PF interrupt can be extremely useful - if it leaves you enough time
to do the things you want to  do.  If  all  you  got  is  50  or  100
milliseconfs  then you have little chance to avoid problems with a CF
card that is being written to. In such a case you  must  design  your
system such that it is robust enough even without such cleanup.

Another technique that has fallen out of favor but is still useful in some
applications is battery backed RAM.  It's relatively expensive, but if
you want fast non-volatile memory it can't be beat.

It depends. Sometimes you may have a  battery,  and  the  power  fail
signal  is  just a warning that leaves you enough time for an orderly
shutdown.

Best regards,

Wolfgang Denk

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