[comp.periphs] SCSI & Sun

paul@sdgsun.UUCP (Paul Emerson) (10/06/87)

I posted this earlier but we had problems with our news forwarding.  This
information is incomplete and somewhat old in light of recent postings,
but here it is anyways.

Subject: Re: Wanted: SCSI Disks for Sun3's
Newsgroups: comp.periphs
References: <104400007@datacube>

in article <104400007@datacube>, berger@datacube.UUCP says:
> Nf-ID: #N:datacube:104400007:000:1971
> Nf-From: datacube.UUCP!berger    Sep 25 18:12:00 1987
> 
> 
> I want to add Disk and Tape to Sun 3 computers.   I would  like to do
> it with as little pain as possible and the priceing should be in line
> with the cost of the computer.   Currently  if I  get a  Sun 3/50 for
> under  $5k,  I  have  to  pay  $8k  for 140Meg  Disk and  60 Meg tape
> subsystem.  The  amount of  disk is  barely enough  and the subsystem
> cost much more than the computer.  
> 
> Has anyone successfully done any of the above?  

Yes.

> Are there any tricks?

Yes.

I have successfully installed a Maxtor XT-3280 (280MB SCSI) on a SUN 3/50.
A few points of interest.
  1. Sun was no help at all.  Unless you count, "What to buy some consulting
     time"?  But I can understand this; they are in the business of selling
      hardware. 
  2. Unless you have a source code licence you'll have to put up with a
     few hassles.  

Background.

	Sun sells what they call "shoebox"	for the 3/50.  Usually this consist
	of a disk drive and a 1/4" tape streamer in an external enclosure, with
	power supply and fan.  This "shoebox" is connect to the 3/50's SCSI
	bus connector via a EIA standard 50 pin cable.  

    What's inside?  My first thoughts about this question were, a SCSI disk.
	But that ansewer is incorrect.  Our "shoebox" consisted of the a
	disk drive only, so I can't tell you about the tape subsystem.  What
	Sun has done is quite simple.  The "shoebox" contains an Adaptec
	ACB-4000A SCSI to ST506 controller board, a ST506 drive (70MB or 140MB),
	power supply and a muffin fan.

	Can you build one of these? Sure no problem.  

	What you need.

	- Enclosure with power supply and fan.  
	  Sun won't sell you one.  I bought a external cabinet designed for an 
      IBM PC/AT, which cost around $145.00, the quality and price vary.  

	- Adaptec ACB-4000A controller.
	  Cost about $110.00

	- ST506 Disk drive, your choice.  I beleive 190MB unformatted is
	  about the largest I have seen.  Just as a test I even connected
	  a 10MB 3 1/2" Rodime. Format, NEWFS, and bang there you are.  Not
	  very practical but it does work.  So pick a disk, the faster the
	  better.  Our "shoebox" from Sun has a Fujitsu formatted to 70MB,
	  you can check the specs and find a drive with simlar specs.

	- 50 pin EIA cable, male DB 50 on both ends.  Price varies, $35.00.

	- 2 50 Pin, DB 50 to 50 pin ribbon connectors.

	- 50 pin ribbon cable

	- 50 pin female ribbon 

	With the above supplies you can build a clone of Sun's "shoebox",
	however the only drawback seems to be disk size.  The largest ST506
	drive I have seen was a 190MB from Maxtor. Due to the apparent size 
	limitation I took another approach.

	Add a SCSI drive to a SUN 3/50.

	Obtain the enclosure and cables mentioned above.
	Get a SCSI drive, I used a Maxtor XT3280 (280MB unformatted).
	Assemble the components.
	The formatting and installtion are the tricky parts.
	To be discussed in a later posting.

	Paul Emerson


-- 
Paul J. Emerson                           Software Design Group, Inc.  
UUCP:...inhp4!codas!sdgsun!paul           800 Trafalgar Ct. Suite 340
CIS: 72355,171                            Maitland, FL 32751
                                          (305) 660-0006

ron@celerity.UUCP (Ron McDaniels) (10/16/87)

An important detail for the do-it-your-self shoebox manufacturer is that
50-pin bulkhead connector on the Sun version. After more than a little
research (the item doesn't appear in the manufacturer's catalog), I found
that it is an AMP 746790-1 IDC subminature "D" plug (IDC is the acronym for
Insulation Displacement Connector, i.e., the type of connector that attaches
to ribbon cable by piercing through the insulation). If you don't worry a
lot about jamming your TV set with stray RFI, a couple of AMP 746789-1
Recepticles and a hank of 50-conductor flat cable will replace the Sun
SCSI bus cable.

The Magnetic tape controller is an Emulex MT02. The magtape drive is a Wangtek
QIC24 type. Hamelton-Avnet sells the MT02 for around $350. I haven't located
an inexpensive source for a QIC24 tape drive.

McD