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Franc Zabkar Franc Zabkar is offline
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Default Flashing LED on old Quantum HDD PCB

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

- Franc Zabkar
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