odd SCSI drives + parts at friend's shop.

[Ethan Dicks]

On 9/15/10, arcarlini at iee.org <arcarlini at iee.org> wrote:
> jim s [jws at jwsss.com] wrote:
>>   I spotted some 3 1/2" form factor drives that I think may be SCSI
>> drives of the narrow "SCA" persuasion... small looking black plastic
>> connector similar to a centronics connector, with what appears to
>> be a central male bar with contacts on it.
>>
> If the drives are the usual 3.5" HDD form factor (as you would find in
> a modern PC for example) and the connector is SCA-80 (i.e. takes up
> 75% or so of the rear width of the drive) then it's almost certainly
> SCSI and all you need is a cheap (~ £5) adapter to hook it up to a
> SCSI-1 or SCSI-2 chain.

Yep.

> If the connector is significantly narrower
> (noticeably less than 50% of the width of the drive) then it is SCA-40
> and will almost certainly be Fibre Channel.

Yep.  And Seagate drives will usually have a "-FC" designator (SCA-80
drives have a "-WC", IIRC)

> Some Sun boxes apparently
> take FC drives and you can make an adapter to hook them up to an HBA
> in a PC.

Yes.  ISTR machines of the SPARCserver 3000 and 5000 era (c. 1996)
might have been able to take the -FC drives directly, or at least
through an available drive shelf product of the same vintage.  Stuff
from the early 1990s was pretty much all parallel SCSI, either narrow
or wide (I forget exactly how old wide-SCSI is).

> Interestingly I always thought that SCA-80 was a relatively recent
> addition to the SCSI fold, but a few months ago I acquired a Seagate(?)
> 1GB drive with an SCA-80 interface. So it's obviously not as recent
> as I thought.

That connector has been around for at least 15 years.  I think I saw a
500MB Seagate drive with an SCA connector once, but those weren't
common.  There were lots of 1GB and 2GB drives with SCA connectors.

The oldest machine I've personally used that had internal SCA
connectors is a SPARC5.

-ethan