> I believe the mp3ar project www.mp3ar.com uses a laptop HD. The
> source code
> was available last time I looked and used a 16F877. Might be code snippets
> there. I've just had a look at the site but it appears their monthly
> bandwidth has been used up at FreeServers so the site cannot be
> viewed until
> next month. Never seen that one before!!!

        Well, just in case anybody is interested I redid part of my code to be more
interactive (I can now read and write registers by hand instead of just
letting the PIC do what I program it), and it seems my problems are due to
these laptop drives I have. It seems that the first read (either CHS or LBA)
works, but any subsequent read (either of the same sector or of a different
one) results in the hard drive hanging the data bus with D0. Nothing I do,
short of toggling the reset line brings it out of this state. I can execute
a read and then do a whole bunch of other things (even a software reset),
but if I read again (command 0x20) it hangs the bus. I say it is these
drives because I have another drive lying around that seems to work
perfectly.

        It might be a moot point anyways, in the end I want to use this inside a
car and it turns out that laptop drivers are much more shock resistant then
desktop drives, at least not enough to be safe in a car. I might just go for
it anyways to see how it turns out, I don't know yet. Anybody ever try going
"outside" of the specs when it comes to hard drives? (mainly in the G shock
area?) Temperature is not a problem since it will be used in a data logging
application and I plan to use a peltier junction to warm the drive up slowly
to spec and then start it up.

        Worst comes to worst I can always just stick a compactflash to IDE adapter
in there and use a CF card, they are MUCH more resilient! Plus my digital
camera uses them... :)

Thanks for any info. TTYL

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