[RndTbl] Need to borrow a SCSI Controller

[Alberto Abrao]

Hello again everyone!

On 2023-01-12 18:08, Trevor Cordes wrote:
> Haha, welcome to the very simple and carefree world of SCSI.
Thank you, I guess? :)
> Ultra160 is 68 pin, LVD and wide.  It says the tape itself can push
> 20MB/s, up to 40 if you luck out on compression.  So really any lvd
> fast wide card should run it at max speed.

Well, it is clearly in no rush whatsoever, eh?

These speeds seem to be for Ultrium 1. Drive and tape are Ultrium 2, so 
that DOUBLES it! I can even feel the breeze on my hair now!

> Did you check if your cable can connect to external box?

One of the ends seems to be able to, yes. The other end looks smaller.

 From my research, the end that goes to the drive may be HD68, and the 
other smaller end may be VHDCI.

I can send some pictures tomorrow, if it helps.

> And the cable
> is the same on both sides?

See above.

>    Should look like a super-dense connector.
> You can match it up with pictures online.
See above, but, for good measure, I will double check tomorrow.
> The IBM spec says they supplied a terminator with the drive.  That
> probably means the drive itself doesn't do optional self-termination
> (bummer).  Is the 2nd connector on the drive case filled with a
> terminator?

Both connectors on the back seem to be bare as far as I can tell.

The terminator may be in a box somewhere... or not.

>   I do not have any 68 pin terminators.  They are rare.
Boo. I may have to go bin diving tomorrow... :(
> Might be easier to find another external 68 pin SCSI device that can do
> self-termination and put that on the end of the chain.  :-)
Would it? :S
> I have these cards that offer 68-pin external connectors you can
> borrow.  Oh, btw, you'll need a box with PCI.  Almost no old-style SCSI
> cards exist for PCIe, certainly none that people have just kicking
> around.

Why, thank you!

I have one PCI capable box ready.

> With external 68-pin:
> IBM RS/6000 PCI 11H8085 AN011H8083 NCR 53C825 chipset sym53c8xx
> Tekram DC-390F Symbios Logic 53C875
> Those 2 will get you only get you 20MB/s, but that should be fine
>
> With only internal 68-pin:
> Adaptec ASC-29160N PCI (suports 160MB/s)
>
> But the internal-only one can be turned into external with:
> SCSI CABLE internal to external 68 pin; 3 drop internal, 1 drop
> external on metal slot bracket; int68-int68-int68-ext68

And would you have all parts for that "daisy chaining from hell?"

> Loving SCSI yet?

All I remember about SCSI is that it was not for mere mortals. It was 
*enterprise grade*, thus ungodly expensive, back in my neck of the woods.

IDE wasn't as complicated, but it wasn't as high end. Easy for me to say 
*now* that I didn't miss much, considering the l33t sp33d5 involved, 
but... I would probably be all over it if I had the opportunity. It's 
not like we were skimping on performance back in those days... and those 
*were* l33t sp33d5 indeed.

> If the Ultrium drive doesn't need to be kept in mint condition, I often
> find it's best to crack open the external SCSI case those things are in,
> take out the bare drive, and plug it into your SCSI setup internally,
> using your normal PS power for it.  Much easier to do internal
> termination.  I have many internal 68 pin cables with terminators
> built-in or tacked on.
Huh...

My plan is to get everything out of the tapes involved and move it to 
newer ones (LTO-8).

I am still checking to see what will be the fate of the drive after I am 
done, so I may be able to do that.

> If you can't find an external terminator or a device that can self
> terminate to put on the chain, then your only choice is converting to
> internal.

The bin awaits...


Once again, thank you, everyone.


Kind regards,
Alberto Abrao