[connect.audit] Hard Disk Drive Select LED Always ON.

hdrw@ibmpcug.co.uk (Howard Winter) (05/07/91)

I have a mchine with a Miniscribe 3650 drive, and its light had always been
on all the time - I'd assumed it was to indicate it was ready.  Then I added
another drive and found that its light came on when it was accessed and went
off immediately.  The first drive's light comes on when you access it and
goes off when you access the _other_ drive.  With only 1 drive there is no
'other' so it stays on - I think you have the same situation - ie. no problem.

Howard.
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hdrw@ibmpcug.Co.UK     Howard Winter     0W21'  51N43'

drp@buhub.bradley.edu (Douglas Pokorny) (05/07/91)

The design of the AT hard disk controller is done in a manner
in which the drive select latches until another drive is made active.
This is claimed to be a feature which increases the speed of the
hard drive. (The computer doesn't have to wait for the disk 
to respons to the drive select if it is always selected)  Whether
or not there is any benefit is of dubious value.  Most clone
controllers have the option to disable this, and use the "normal"
XT style of drive accesses.  Unless you are staring at the front
of the drives, and find the constant light anoying, don't bother
with it.


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