Is hot swapping TrueIDE mode Compact Flash possible?

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Hi.

I am using an off the shelf PC motherboard with a TrueIDE boot flash.
A RAM-resident system loads from the CF card.  From that point on the
CF card is not used (no filesystems mounted).


Is it electrically ok to swap an idle card?  Will the new card
configure itself into TrueIDE mode upon insertion?

I haven't mentioned an operating system on purpose.  Host software I
can deal with - it's the CF card itself and its IDE connection that I'm
concerned about.


Tips, advice, scary stories appreciated.


Regards,
Paul.


Re: Is hot swapping TrueIDE mode Compact Flash possible?
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It is explicitly not supported in the CompactFlash specification. The
power supply pins are mechanically sequenced before any control or data
lines (look at the connector), therefore the card will not see TrueIDE
strapping at powerup.

If you attempt it, you'll find it does work sometimes, particularly if
you ram the card in quickly. It's not something you want to design into
your user interface, though.


Re: Is hot swapping TrueIDE mode Compact Flash possible?

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Thanks for that.  I'd heard before that it wasn't supported, and so
it's not a requirement for the project.  However I had read some
comments on a Linux board regarding changes to their IDE driver to
possibly support it in the future and it started me wondering if it was
a software issue or a hardware one.


Thanks again for the quick response.

Regards,
Paul.


Re: Is hot swapping TrueIDE mode Compact Flash possible?
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Many devices with a CF slot run in IDE mode have a FET switching the
power rail to the card so that it can be power-sequenced after full
insertion, precisely so hot-swapping can be supported.


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