Date   : Wed, 30 May 2012 17:11:07 +0200 (BST)
From   : johan@... (Johan Heuseveldt)
Subject: Setting jumpers SCSI IDs

Hi Jules,

On Tue 29 May, Jules Richardson wrote:

[snip]

> Incidentally, I don't recall ever seeing a SCSI device where the removal of 
> an ID jumper signified a '1' and the presence of one indicated a '0' (which 
> I think Johan was saying has typically been his experience) - it's always 
> the other way around (all jumpers off = ID 0, and adding jumpers signifies 
> bit-set in that position).  That's not to say I haven't seen them "Johan's 
> way around", just that I don't remember it ;)

I wonder myself too! ;-)

I've checked several drives, but certainly not all.

For a Seagate ST157N I'd expected the opposite way, but
searching Internet suggests the normal way; a fitted jumper
being 1. Testing turns out to be weird, as several jumper
settings still keeps the SCSI ID being 0, after power cycling.
Verifying the drive gives about 60 read errors!

Also tested a NEC 3841, and this was error free. During a verify,
there are only a few moments of a little bit more noise. Probably
some blocks remapped. Quite silent as well!

I suppose these are not really old drives?


Well, perhaps I was confused with using jumpers to zero a line,
which otherwise is high by resistor to VCC.


Thank you all,
Johan

-- 
Johan Heuseveldt <johan@...              >
  aka  waarland

  The best place is a Riscy place

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