BARRY MARTIN wrote:
> Hi Ky!
> KM> Well, this message is older than dirt...
> You're supposed to log in more frequently than once a century!
Oh, is that it? Who knew!!
> > The clock is powered by the 5v from the USB, so plugs in to one of the
> > ports. Currently the 5v is reduced to 3v by the voltage divider
> > circuit.
> That's the problem: the clock is running slow and so that's why you're
> just getting the message!!
Now you're talking to yourself. ;) Or someone, anyway, wasn't me!
> KM> I lately discovered something odd about USB... the setup is this:
> KM> USB Hub (no power)
> KM> 1) hard disk (no power)
> KM> 2) hard disk (with external power)
> KM> So long as #2 is plugged in, #1 is powered even if nothing is
> KM> attached to anything else (no other power sources). Didn't
> KM> realise they shared!
> So #1 is getting its power via #2? Yes, sounds a little strange but the
> electrons don't care where the source is. Humans are expecting the
> source to be the hub but once electricity is put on the 'rails' it's
> there and goes in all directions. If AC might be a problem with
> phasing, but as DC and polarized no problem.
Yeah, I was expected it was gated one direction, but apparently this
isn't the case. Makes me wonder what happens if a USB device plugged
into the computer should happen to get overpowered... I'm not sure I
like this idea, come to mention it.
> KM> Just had to retire the oldest hard disk in the house that was
> KM> still in use... almost 18 years old!! Starting to have a little
> KM> hitch in its getalong, locks up if it's asked to do too much at
> KM> once. Wasn't being asked to do much, since all that box does is
> KM> DOS. What's really amazing is that it's an IBM HD !!!
> IBM does build some sturdy stuff! As it locks up if asked to do too
> much at once, my guess is a mechanical issue: the heads can't get in
> position fast enough.
It had been working fine for a long time, doing the exact same thing,
and only developed this problem in the past month or so. Also started sometimes
taking a long time for the system to recognise the drive at
startup, which tends to indicate a failure other than the platters (was
not getting data errors of any sort). Probably got a data pileup when
some circuit failed to respond in a timely manner, hence the "busy" thing.
Which is amazing because if there's one place IBM failed spectacularly,
it was in hard drives (remember the fractured platter issue?). This is
the only live IBM HD I've ever seen!
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