Franc Zabkar writes:

On Fri, 2 Dec 2011 13:26:36 GMT, lid
(Windmill) put finger to keyboard and composed:

If I can't find an explanation of the flash code, I'll try the rapping
technique.

If the drive has a stiction fault, then you should see pulses at the
motor windings as the motor controller attempts to kickstart the
drive. I believe this is called "spin buzz".

Alternatively, there will probably be a current sense resistor, or an
array of parallel connected sense resistors, to sense the motor
current. You could measure the voltage at this point. Note that there
will also be a current sense resistor for the voice coil.

FWIW, here is my database of motor controller IC datasheets:
http://www.users.on.net/~fzabkar/HDD...r_Control.html

I don't know if this tutorial will be of any help to you ...
http://www.users.on.net/~fzabkar/HDD...l_SP0411N.html

That's a very impressive collation of information. I've kept a copy for
future reference, though hopefully I won't need it.
Used to work on ancient mainframes long ago, so in theory I can still
understand the details. If I can just find my glasses.


--
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