Re: hardware question: scsi disk and SS10

[Mouse <mouse%Rodents-Montreal.ORG@localhost>]

> I want to put a newer disk in my sparcstation 10, the one I had up to
> now is a 4GB disk, 50pin, which are exceedingly rare to find.
> Anybody has a SS10?

I've got at least a few 10s.

> 68pin wide disks are easier to find, actually I got a "new old
> stock".  I have a 68-50pin SCSI adapter (and just to be sure I bought
> one off ebay which is specified to have termination).

It might even actually have it!  (In view of the below, I'd guess it
probably does.)

> - The disk is seen (probe-scsi and is bootable) if inside an external
> enclosure
> - The disk is seen (probe-scsi and is bootable) if put inside another
> SparcStation, an older IPC
> - The disk is not seen and can't be booted if connected to the
> internal connectors of the SparcStation 10, I tried both connectors

Did you check that the cable is firmly seated at the motherboard end?
I just opened up a handy 10 and the cable was loose enough I could feel
it seat better upon pressing down on the connector, even though it
didn't look loose.

> has anybody attempted something like this?  I tried a bit with the
> HDD configuration pins.  I suspect it is a termination problem,
> because the SS10 is tricky about that.

Is your adapter capable of being told to _not_ terminate?  It looks to
me as though the internal SCSI chain probably does not expect disks to
carry termination.

> The disk does work in the SCSI-1 compatibility mode, since it works
> in the enclosure or the IPC.

This is one of the really nice aspects of SCSI....

> Perhaps the SS10 is trying to run it in "fast scsi or something"?

Possible, but in my (limited) experience, trouble there would lead it
to fall back to slower operation, not fail entirely.

Especially since you say it's "not seen" - IIRC device location always
operates at slow async speeds.

> SCA-80 discs are easier to find apparently., so SS4/SS5/SS20 and
> Ultras don't suffer from this.

Well, in the larger sizes, yes.  I've got lots of 50-pin drives, but,
apparently like you, few of them are above the 1-2G range.

/~\ The ASCII				  Mouse
\ / Ribbon Campaign
 X  Against HTML		mouse%rodents-montreal.org@localhost
/ \ Email!	     7D C8 61 52 5D E7 2D 39  4E F1 31 3E E8 B3 27 4B