I have an old 5.25" Quantum Bigfoot CY6.4 hard drive which I want to
use in an old PC.

It was working some months ago when I hooked it up to a USB adaptor on
a Ubuntu PC and backed up its contents.

But now it isn't recognized by the OS (various old Linux and new Ubuntu
Linux versions), neither on the old PC nor on the USB adaptor.

'dmesg' shows info for a different drive (which works), but nothing for
the Quantum drive.

There's a little green SMD LED on the PCB which is steadily lit at
first (and the BIOS displays its capacity, C/H/S, etc. so can obviously
read the drive) but which then begins to flash repeatedly in a pattern
of 8 flashes - short pause - 10 flashes.

Not sure if that could be something built into the firmware, or some
pattern of repeated access attempts by the kernel.

I've tried it jumpered as master and as slave, and with an old 40
conductor ribbon cable and a new 80 conductor cable, on its own and
with a CDROM drive. But nothing works.

I'm puzzled. Is the LED a disk activity light? There's something about
one I/O line being sometimes shared as a 'slave select' and a 'disk
activity' line, but I can't see what that would have to do with the
problem.

I have a very vague and possibly unreliable memory of having to tinker
a bit, or do something special, when the drive was new, but no clear
recollection.

Going to see if I can find any HD diagnostic program which might report
something, but meanwhile, does anyone know what the flash pattern
indicates?

--
Windmill, Use t m i l l
J.R.R. Tolkien:- @ O n e t e l . c o m
All that is gold does not glister / Not all who wander are lost