Franc Zabkar writes:

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

Does the same thing happen if you power up the drive without the
interface cable?

Yes. I should have thought of that. So it's the drive's firmware which
is generating the flash pattern

If you disconnect one of the RAM buffer pins, does the LED pattern
change? Doing so should result in a Sector Buffer Error (error code
03h).

Not sure where I would do that. I haven't disassembled the drive and
don't have a full technical manual for it, and I'm not sure where I
would be able to disconnect (and then later reconnect) a single pin on
a tiny SMD.

Should the flash pattern be interpreted as hex code 8A ? Do you have
something which lists these codes, or a link to something which does? I
found some information by Googling, but nothing about error codes from
the LED.

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