Handling power failure - MPC5200

[Wolfgang Denk]

In message <005a01c4c349$7949b8c0$0301a8c0 at chuck2> you wrote:
> 
> >What I've seen is marketing bullet points saying the cards can survive a
> >power loss event with no loss of data, but when I read the >detailed CF
> >specification, the disclaimer was that power had to be held up for X mSec (I
> >forgot what X was, 2mSec or 10mSec most likely) after the last write
> >operation.  The marketing bullet point was exactly that: marketing.  The
> >real requirement levied on the user
> >(you) was that you had to have X mSec power hold up after the last write
> >operation (i.e. a X mSec power fail warning with no write >operations after
> >the PF warning).  The hold-up requirement gave the CF internals enough time
> >to complete a flash write cycle.
> 
> One simple use for the power fail interrupt would be to just turn off
> interrupts and loop until power fail.
> This would insure that a write or erase operation completed fully.

Maybe it would - but do you know exactly how long a  write  operation
will  take?  I  haven't  seen  such information in the specs I had so
far...

Best regards,

Wolfgang Denk

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