Subject: SGI hardware Frequently Asked Questions (FAQ)
From: [email-masked] (The SGI FAQ group)
Newsgroups: comp.sys.sgi.misc,comp.answers,news.answers

Archive-name: sgi/faq/hardware
Last-modified: Wed Mar  9 16:12:38 CST 1994

    SGI hardware Frequently Asked Questions (FAQ)

This is one of the Silicon Graphics FAQ series, which consists of:

    SGI admin FAQ - IRIX system administration
    SGI apps FAQ - Applications & compilers
    SGI graphics FAQ - Graphics and user environment customization
    SGI hardware FAQ - Hardware
    SGI misc FAQ - Introduction & miscellaneous information
    SGI performer FAQ - IRIS Performer
    SGI pointer FAQ - Pointer to the other FAQs

Read the misc FAQ for information about the FAQs themselves.  Each FAQ
is posted to comp.sys.sgi.misc and to the news.answers and comp.answers
newsgroups (whose purpose is to store FAQs) twice per month.  If you
can't find one of the FAQs with your news program, you can get it by
anonymous FTP from one of these sites:

    rtfm.mit.edu:/pub/usenet/comp.sys.sgi.misc/
    rtfm.mit.edu:/pub/usenet/news.answers/sgi/faq/
    rtfm.mit.edu:/pub/usenet/comp.answers/sgi/faq/
    viz.tamu.edu:/pub/sgi/faq/

Note that rtfm.mit.edu is home to many other FAQs and informational
documents, and is a good place to look if you can't find an answer
here. If you can't use FTP, send mail to [email-masked] with
the command 'send usenet/news.answers/ftp-list/faq' on a line by itself
in the text, and it will send you a document describing how to FTP by
mail. You can also read a hypertext version of the FAQs at

    http://www.cis.ohio-state.edu/hypertext/faq/usenet/sgi/top.html

The SGI FAQs are freely distributable and wide circulation is encouraged.
The contents are accurate as far as we know, but the usual disclaimers
apply. Please send additions and changes to [email-masked].

Topics covered in this FAQ:
---------------------------
   -1- GENERAL INFORMATION
   -2- Where can I get a copy of SGI's Periodic Table of the Irises?
   -3- What third-party vendors sell thus-and-such for SGIs?
   -4- Where can I get used SGI machines?
   -5- What is my old SGI machine worth?
   -6- What about my IRIS 2000 or 3000?
   -7- Should I shut off my Iris at night?
   -8- MEMORY
   -9- Can I mix 1MB and 2MB SIMMS in my 4D/20 & 4D/25 Personal IRISes?
  -10- Can I add 4MB SIMMS to my 4D/20 or 4D/25 PI?
  -11- How many 4MB SIMMS can be put into an Indigo?
  -12- How can I find a bad SIMM?
  -13- MONITORS AND VIDEO HARDWARE
  -14- My monitor is maladjusted in some way. How to fix it?
  -15- Can I have 2 graphics displays on my Indigo?
  -16- What do I need to do stereo on an Onyx/RE2?
  -17- What new (higher performance) video options are available?
  -18- Can I use my SGI monitor on my PC?
  -19- Can I use my PC monitor on my SGI?
  -20- What video formats, scan rate, etc. do SGI monitors support?
  -21- STORAGE DEVICES
  -22- What do all these SCSI technical terms mean?
  -23- How many SCSI devices can I have on an Indigo?
  -24- How do I install external SCSI disks on my SGI?
  -25- What kind of DAT drive does SGI sell for the Indigo?
  -26- Can I use a 3rd-party cartridge tape drive on my Indigo?
  -27- Which Exabyte drives work with SGI systems?
  -28- How to connect my 3rd-party tape drive to my SGI?
  -29- How should I set up my tape drive so tar's 'r' and 'u' options
       work?
  -30- What do I do when I get checksum error reading a tar tape?
  -31- How can I recover a partially overwritten tar tape?
  -32- When and how should I clean my tape drive?
  -33- How can I eject a jammed tape?
  -34- Can I use a non-SGI CD-ROM on my SGI?
  -35- Why can't Joe User eject his CD-ROM?
  -36- How can Joe User mount and unmount his MO disk?
  -37- Why do SGI SCSI controllers have host ID 0 instead of the usual
       7?
  -38- EVERYTHING ELSE
  -39- How long can my monitor/keyboard/mouse cables be?
  -40- What is "/dev/tport" used for?
  -41- How fast is the Indigo parallel port?
  -42- What are the differences between the Indigo R4000 and Indigo2?
  -43- What high speed interfaces are available for Onyx?
  -44- Why doesn't my modem work?
  -45- What mice can I use with my Indigo or Indigo2?
  -46- What about uninterruptable power supplies?

----------------------------------------------------------------------

Subject:    -1- GENERAL INFORMATION
Date: 09 Jan 94 00:00:01 EST

The next few items discuss general questions about hardware.

------------------------------

Subject:    -2- Where can I get a copy of SGI's Periodic Table of the
                Irises?
Date: 10 Dec 93 00:00:01 EST

SGI Direct (see the misc FAQ for phone numbers) and your friendly
neighborhood salesbeing is guaranteed to have the latest. Nonetheless,
the misc FAQ lists the locations of FTPable Postscript versions.

------------------------------

Subject:    -3- What third-party vendors sell thus-and-such for SGIs?
Date: 17 Feb 94 00:00:01 EST

Look in the misc FAQ for a pointer to lists of third-party disks,
memory, magneto-optical drives and general vendors.

------------------------------

Subject:    -4- Where can I get used SGI machines?
Date: 18 Feb 94 00:00:01 CST

The SGI Systems Remarketing group makes used SGI machines available to
sales representatives.  If you want to buy a used SGI machine, ask your
local sales rep or call SGI Direct (see the misc FAQ for phone numbers).

[email-masked] (Boris Levitin) lists some other remarketers:

    Concorde Groupe                         800-437-8621, 404-423-0070
    Concorde Groupe, fax                    404-426-8130
    Falcon Systems, Jeff Geiger             800-326-1002
    Minicomputer Exchange, John McFarland   408-733-4400
    R-Squared, Tony Sciacca                 800-777-3478
    Security Computer Sales                 612-227-5683
    Sun Valley Technical Repair, Joe Ferris 408-224-6261
    X-Systems, Jon Nies                     800-886-5343, [email-masked]
    X-Systems, fax                          303-443-7440
    XS International                        404-874-1212

------------------------------

Subject:    -5- What is my old SGI machine worth?
Date: 26 May 93 00:00:01 CST

Thanks to Thomas Sippel-Dau <[email-masked]> for this summary:

Since computer technology has been improving so rapidly, this is
difficult to answer generally.  But you can take the following
approches to get somewhere near a realistic estimate.

1.  The Book Value.

This assumes the computer is an investment object which is written down
over a certain time.  At the end of this time it is assumed that the
residual value will pay for scrapping the object, so you do not have to
pay someone to take it away.  About 5 years seems reasonable for
computers.

    Value   the current value
    Price   the original price
    n       the age of the machine in months
    p       depreciation rate 1.6% (for 62.5 months useful life)

1.1 Linear method:     Value = Price * ( 1 - n * p )
1.2 Degressive method: Value = Price * ( 1 - 2 * p ) ** n

In the first 4 years the degressive method will give lower values.

Once the degressive monthly depreciation is lower than the linear one,
you should sell the machine and buy a new one, otherwise you pay more
tax than you need to (talk to your accountants first, they should know
the exact depreciation rate and method).

2.  Comparative method.

Get the new price of a similar current machine.  Multiply the current
price by any usefulness multipliers.  For example:

    An Indigo R3000 server costs $8000 (N.B. NOT the real price) An
    Iris 4D/25 is about half the speed of it

    Then the current value of the 4D/25 cannot be more than $4000
    regardless of what the book value says.

For this you must strip or enhance the machine to a current standard.

Say you take the price of an Indigo with 432 disk Mbyte and 16 Mbyte
memory to assess the residual value of a 4D/25 with eight Mbyte memory
and 330 Mbyte hard disk.  You will arrive at the price after you have
upgraded the the 4D/25 to 16 Mbyte.

Since both machines are not very useful (stand alone) with so little
disk space, you can allow for the difference in disk space when you
calculate the price of the whole running system.

For this method the old system must be able to run current software
usefully.  A system that does not run current software has no value,
but see below.

You should also take account of the maintenance cost for about three
years, which is when a system you buy now would be due for replacement
according to  the book value method.

3. Components and options.

You can view the system as an assembly of useful parts, such as
monitor, keyboard, disk drives, system box, electronics module.  If you
have extra memory or disks (over and above the currently useful
minimum), you can value them at about 80% of the price you currently
have to pay third party suppliers.

4. Residual use value.

If you can find a dedicated use for an old general purpose machine,
then this could give you a final number.  However, you need to allow
for any work you have to put in to get to that state, and to keep the
system there.  You will also find that only reasonably large
organisations have such dedicated uses.

Finally, a word about maintenance:

If you have one system only, and you cannot afford to lose it, you need
to take maintenance, regardless of how much it is.  From about 5
systems you can save yourself maintenance if you can afford to lose the
odd system and load its uses onto the remaining ones.  But remember
that rescheduling people often meets resistance, and keeping people
idle because of a system failure is extremely expensive.

------------------------------

Subject:    -6- What about my IRIS 2000 or 3000?
Date: 27 Feb 94 00:00:01 EST

Look in the misc FAQ for pointers to the IRIS 2000/3000 mailing list
and FAQ.

------------------------------

Subject:    -7- Should I shut off my Iris at night?
Date: 13 Feb 94 00:00:01 EST

(Home users often ask this.) No, you should not. The hardware is
designed for continuous use, and IRIX schedules cleanup tasks for the
early morning. (See the cron(1M) and crontab(1) manpages and the files
in /usr/spool/cron.) Disks, tapes, CD-ROMs etc. consume little power
when idle and should NEVER be turned off or on (or connected or
disconnected) when the system is running. You may want to turn off your
monitor to save power (they use a lot), but if you use a screensaver
there is no other reason not to leave it on.

------------------------------

Subject:    -8- MEMORY
Date: 09 Jan 94 00:00:01 EST

The next few items discuss adding memory.

------------------------------

Subject:    -9- Can I mix 1MB and 2MB SIMMS in my 4D/20 & 4D/25 Personal
                IRISes?
Date: 20 May 93 00:00:01 CST

From PIPELINE March/April 1992, page 18:
You can use either 1MB or 2MB SIMMs in these systems.  If you mix 1MB
and 2MB SIMMs, all sixteen memory slots must be filled.

------------------------------

Subject:   -10- Can I add 4MB SIMMS to my 4D/20 or 4D/25 PI?
Date: 20 May 93 00:00:01 CST

The short answer is "maybe".  Read on.

Thanks to Michael Portuesi <[email-masked]> for this
helpful summary:

The 4D/2* has 16 memory slots.  You get access to them by removeing the
right plastic cover and the metal shield underneath (box seen from the
front).  The slots are in the upper, left corner (box now seen from the
right).

The slots have to be populated by SIMMs (some kind of industry
standard).  I think 80 or even 100ns is allright, but take a look at
the speed of your own SIMMs.

SIMMs should always be mounted in groups of four.  In a plain 8MB 4D/20
you have eight 1MB SIMMs.  They are placed in slots A and B in this
figure:

    ABCD ABCD
    ABCD ABCD

If you upgrade to 16MB using eight more 1MB SIMMs you simply insert the
new SIMMs in slots C and D.  If you are going to mix different SIMMs
you should always have the the same type of SIMM in slots with the same
letter.

As far as I know, the SGI 32MB memory upgrade is sixteen 2MB SIMMs, and
they are mounted in all the slots.  Now, I have been told (but haven't
tried it) that it is possible to mix 1 and 2MB SIMMs.  The important
point is that the 2MB SIMMs should be in the lowest numbered slots.  To
get 24MB you should populate the slots as shown (signatures are, 1 =
1MB SIMM, 2 = 2MB SIMM, 4 = 4MB SIMM, . = empty slot):

    2211 2211
    2211 2211

The good news is that you can get 4MB SIMMs from third-party vendors
outpricing the 2MB SIMMs available from SGI.  To get 32MB you mount 8
4MB SIMMs like this:

    44.. 44..
    44.. 44..

The bad news is that you cannot mix 4MB SIMMs with 1 or 2MB SIMMs
(leaving a lot of spare SIMMs) and even worse, not all 4MB SIMMs will
function properly.

Among the "good" SIMMs are those from Toshiba.  They should look
something like this (information I got from a news article posted by
Chris Miller <[email-masked]>):

          module ID tags:                 chip numbers:

   --------------          ---------      TOSHIBA
  | TOSHIBA      |        | 9025AAA |     TC514100J-80
  | THM94000S-80 |        | JAPAN   |     JAPAN 9020HDK
   --------------          ---------

Among the "bad" SIMMs are those from Hitachi:

                                          chip numbers:

                                          JAPAN R200
                                          9026 2NN
                                          HM514100JP8H

Other memory configurations that we have tried are (0 = empty slot, 1 =
1MB SIMM, 2 = 2MB SIMM, H = 4MB Hitachi SIMM, T = 4MB Toshiba SIMM):

	1100	1100		Came up as 8MB (correct)
	1100	1100

	1111	1111		Came up as 16MB (correct)
	1111	1111

	TT11	TT11		Came up as 64MB (wrong)
	TT11	TT11

	T000	T000		Came up as 16MB (correct)
	T000	T000

	TT00	TT00		Came up as 32MB (correct)
	TT00	TT00

	HH00	HH00		Came up as  0MB (wrong!!)
	HH00	HH00

	TH00	TH00		Came up as 32MB (correct)
	TH00	TH00

	TTH0	TTH0		Came up as 48MB (correct)
	TTH0	TTH0

	TTHH	TTHH		Came up as 64MB (correct)
	TTHH	TTHH

	11TT	11TT		Comes up as 16MB
	11TT	11TT

It appears as though the machine checks the first bank of chips (port
0) to determine the chip size and assumes that the rest are the same.
The Hitachi 4MB SIMMs are NOT correctly detected.

It is important that the 4MB SIMMs in slot A are 'good'. Then you are
free to use "bad" 4MB SIMMs in the rest of the slots (this is my
experience), and it is possible to upgrade to 64 MB populating all the
slots with 4MB SIMMs.

When you do the actual seating of the SIMMs you should take precautions
(wear a static strap, work on a static pad) not to damage the memory.
Sometimes you will have to reseat a module.  If a SIMM is not properly
seated it will probably show up on the diagnostics terminal (if you
have one attached) during power on.

After a succesful power on you should enter the PROM monitor and issue
the 'hinv' command.  This should tell you how much memory you have (or
how much the 4D/2* believes it has).  If this is correct you are ready
to boot.

------------------------------

Subject:   -11- How many 4MB SIMMS can be put into an Indigo?
Date: 20 May 93 00:00:01 CST

One (1) set.  Says Dave Olson <[email-masked]>:
Due to a design flaw, only one set of 4MB SIMMs (16 MB per bank) can be
used in an R3000 Indigo, 4D/30 and 4D/35.  This limitation doesn't
apply to the 2 MB or 8 MB SIMMs.

------------------------------

Subject:   -12- How can I find a bad SIMM?
Date: 20 Feb 94 00:00:01 EST

Articles in the Mar/Apr 92 and May/Jun 93 Pipelines describe how to
find bad SIMMs in Personal Irises. The PROM diagnostics on Indigos and
newer can find them for you.

------------------------------

Subject:   -13- MONITORS AND VIDEO HARDWARE
Date: 09 Jan 94 00:00:01 EST

The next few items discuss monitors and video hardware.

------------------------------

Subject:   -14- My monitor is maladjusted in some way. How to fix it?
Date: 27 Feb 94 00:00:01 EST

Get these handy writeups on monitor adjustment:

viz.tamu.edu:/pub/sgi/hardware/adjusting-your-monitor
viz.tamu.edu:/pub/sgi/hardware/adjusting-your-monitor-II

------------------------------

Subject:   -15- Can I have 2 graphics displays on my Indigo?
Date: 18 Feb 94 00:00:01 CST

The Dual Headed IRIS Indigo with Entry Graphics (W-RPC-DH) sounds like
what you want.  It has two Entry Graphics subsystems and two 16"
monitors.  Contact SGI Direct (see the misc FAQ for phone numbers) for
more information.

Starting with Irix release 5.1.1.2, there is also support for dual-head
configurations on Indigo-2's.  Both heterogeneous (Extreme-XL) and
homogeneous (XL-XL) hardware combinations are possible.

------------------------------

Subject:   -16- What do I need to do stereo on an Onyx/RE2?
Date: 14 Jun 93

Paul Spencer <[email-masked]> illuminates us with:

You just need the shutter glasses (and the emitter, which comes with
the glasses). This is available as a kit from SGI.

The standard SGI RealityEngine monitor can do stereo; you don't need a
special CRT.

Demo programs and sample source code are part of every IRIX release.

------------------------------

Subject:   -17- What new (higher performance) video options are
                available?
Date: 14 Jun 93

Stan Jensen <[email-masked]> points out:

At the NAB show in April SGI announced three video products:

    Galileo: a video I/O option for the "non-Entry" Indigoes 
    Cosmo: a JPEG compression board for the Indigoes
    Sirius: a video I/O option for the Reality Engine and Onyx

Stan also reminds us to call SGI Direct whenever we are in doubt!

------------------------------

Subject:   -18- Can I use my SGI monitor on my PC?
Date: 28 Jan 94 00:00:01 EST

Rick McLeod <[email-masked]> writes:
This depends on the SGI monitor.  PCs want multifrequency/
multiscanning/multisyncing monitors.  Earlier SGI platforms supplied
fixed frequency or dual scan mode monitors.  These will not work on
PCs.  Some current SGI machines (Indy, Indigo2, Onyx) ship with
multiscan monitors.  These will most likely work with a PC, but make
sure that the monitor gets the proper sync signal.

------------------------------

Subject:   -19- Can I use my PC monitor on my SGI?
Date: 28 Jan 94 00:00:01 EST

Rick McLeod <[email-masked]> writes:
The PC monitor must be able to handle a 1024x768 non-interlaced signal
to be used with Indigo starter graphics or Indy.  Most of the SGI
systems operate at 1280x1024 non-interlaced.  Most PC monitors will not
be able to deal with the scan rates required to display a stereo
image.

------------------------------

Subject:   -20- What video formats, scan rate, etc. do SGI monitors
                support?
Date: 20 Feb 94 00:00:01 EST

It depends on the monitor.  See the Sep/Oct 93 Pipeline (and a
correction on p. 26 of the Nov/Dec 93 Pipeline) for a tabulation of the
characteristics of most types of SGI monitors.

------------------------------

Subject:   -21- STORAGE DEVICES
Date: 09 Jan 94 00:00:01 EST

The next few items discuss storage devices. Tapes, mostly.

------------------------------

Subject:   -22- What do all these SCSI technical terms mean?
Date: 12 Feb 94 00:00:01 EST

Look in the misc FAQ for a pointer to the SCSI FAQ.

------------------------------

Subject:   -23- How many SCSI devices can I have on an Indigo?
Date: 26 May 93 00:00:01 CST

You can have 7 SCSI devices, and as long as you have clean cabling, and
one (and only one!) SCSI terminator at the end of the chain, and keep
total cable length under 6 meters, there should be no problems, as far
as the Indigo's bus itself goes.

On an Indigo2, you can have 7 devices on the external SCSI bus, and up
to 3 devices on the internal bus.

------------------------------

Subject:   -24- How do I install external SCSI disks on my SGI?
Date: 02 Feb 94 00:00:01 CST

The basic procedure is to use 'fx' to format and label the drive (the
label contains the partition layout), use 'mkfs' to create the empty
filesystem, create the mount points and put the proper entries into
/etc/fstab. The IRIX Site Administrator's Guide describes this in
detail.

The graphical Disk and File tool assumes you bought your drive from
SGI, in which case the 'fx' and 'mkfs' parts have already been done.
It also assumes you want to use the entire drive as a single
partition.

------------------------------

Subject:   -25- What kind of DAT drive does SGI sell for the Indigo?
Date: 26 May 93 00:00:01 CST

The Indigo DAT drive is an ArDAT Python 4320.

The drive SGI sells is completely standard 3.5" form factor hardware
(no compression), but has firmware that so far ARDAT is selling only to
SGI to provide audio over SCSI support, and to fix some bugs.

------------------------------

Subject:   -26- Can I use a 3rd-party cartridge tape drive on my Indigo?
Date: 26 May 93 00:00:01 CST

The Tandberg and Archive QIC24 and QIC-150 drives both work just fine
on the Indigo (both come in external versions), as do the Wangtek and
Tandberg QIC-1000 drives (as of this quarter, and 4.0.5F or later).

------------------------------

Subject:   -27- Which Exabyte drives work with SGI systems?
Date: 26 May 93 00:00:01 CST

Dave Olson <[email-masked]> says:
First, the 8200 (2.3 Gb).  The original version we qualified was 100%
stock from Exabyte.  It had some problems on the ESD machines at power
on, because of the somewhat non-standard way it handled the send-diag
SCSI command.  The current rev (252T) we ship is also standard firmware
from Exabyte (to the best of my knowledge), and fixes that problem, and
is also more robust in the face of servo problems.

The 8500 (5 Gb) isn't fully qualified (by SGI) yet, and there is some
argument over whether we will ask for custom firmware; I think we are
definitely slanting towards standard firmware.  The gotcha here is that
Exabyte has released so many firmware revs for the 8500, that the word
'standard' is somewhat of a joke.  I've lost touch with that effort a
bit, so I don't know what firmware rev we are currently working with.

4.0.1 is the first IRIX release with support for the 8500, earlier
releases will work to varying degrees with different 8500 firmware.

------------------------------

Subject:   -28- How to connect my 3rd-party tape drive to my SGI?
Date: 09 Jan 94 00:00:01 CST

Only part of the voluminous literature on the topic may be found at

    viz.tamu.edu:/pub/sgi/hardware/3rd-party-DAT-drive
    viz.tamu.edu:/pub/sgi/hardware/exabyte-howto-for-sgis

------------------------------

Subject:   -29- How should I set up my tape drive so tar's 'r' and 'u'
                options work?
Date: 09 Jan 94 00:00:01 EST

Sara Kunz <[email-masked]> writes:
Use the variable block size tape devices. These are called
/dev/rmt/tps0d#nsv and /dev/rmt/tps0d#nrnsv, where '#' is the tape's
SCSI device number. If the tape drive is properly attached (it should
appear in 'hinv's listing), saying '/dev/MAKEDEV tps' should create the
devices for you. If the tape drive in question is the tape drive with
the lowest SCSI ID, '/dev/MAKEDEV tapelinks' will link the appropriate
devices to /dev/tape and /dev/nrtape.  Note that appending is
physically possible only on 9-track and DAT tapes.

------------------------------

Subject:   -30- What do I do when I get checksum error reading a tar
                tape?
Date: 11 Jun 93 00:00:01 EST

Glenn Randers-Pehrson <[email-masked]> says:

You are probably trying to read a non-byte-swapped tape on a
byte-swapping device, or vice versa.

Tar tapes written on SGI's QIC cartridge drive, using the default
device name "/dev/tape" are in byte-swapped format.  SUN tapes are
usually non-byte-swapped.

On the IRIS, you can read non-byte-swapped tapes with

    tar -xvf /dev/tapens

and you can write non-byte-swapped tapes destined for a Sun with

    tar -cvf /dev/tapens [directory_or_filename[s]]

On the SUN, you can read byte-swapped tapes with

    dd if=/dev/rmt0 conv=swab | tar -xvf -

Read the tar(1) (DIAGNOSTICS section) and tps(7M) manpages for the gory
details.

------------------------------

Subject:   -31- How can I recover a partially overwritten tar tape?
Date: 10 Dec 93 00:00:01 EST

People often overwrite the beginning of large tar archive, leaving the
first bit of the tape overwritten and the rest presumably intact. This
is usually NOT recoverable.

However, if you're feeling lucky, you might (says Dave Olson
<[email-masked]>) try something like 'mt fsf 4; mt bsf 2; tar xe' or
'mt fsf 4; mt bsr 2; tar xe'.  You might also try 'tar cv foo', where
'foo' is slightly bigger than what you overwrote the archive with the
first time, and pull the plug on the tape drive before it writes the
EOF. Then power it back up and try 'tar xe'.

If this sounds unlikely to work, you're right. Don't let it happen; use
the write protect tab.

------------------------------

Subject:   -32- When and how should I clean my tape drive?
Date: 20 Feb 94 00:00:01 EST

9-track and QIC drives should be cleaned every 8 hours of use, or more
often when using many new tapes, and certainly when the number of
"recoverable errors" gets uncomfortably high. See the Nov/Dec 91
Pipeline or the "IRIS Software Installation Guide" for a detailed
cleaning procedure. Briefly, shut the drive down and swab the head with
isopropanol and a lintless cloth.

8mm and DAT drives need to be cleaned every 30 hours of use, using a
commercial cleaning tape according to the instructions.

------------------------------

Subject:   -33- How can I eject a jammed tape?
Date: 09 Jan 94 00:00:01 CST

Read viz.tamu.edu:/pub/sgi/hardware/ejecting-jammed-tape.

------------------------------

Subject:   -34- Can I use a non-SGI CD-ROM on my SGI?
Date: 14 Feb 94 00:00:01 EST

4D20, 25, 70, 80 and 85s and most Power Series machines can boot only
from SGI CD-ROMs. Older machines can boot only from a local tape drive
or over the network. Newer machines (4D30 and 35s, Indigos, Challenges,
Onyxes, Indys, etc.) have smarter PROMs and can boot from at least some
third-party CD-ROMs, for example the Sony and Toshiba drives intended
for Suns. The rest of this entry discusses what qualifies a drive for
4D30s and later.

Dave Olson <[email-masked]> of SGI says,
The basic requirement for Indigos is that the drive be set to use a 512
byte block size.  Since Indigos don't reset the SCSI bus on reboot or
halt, you *might* be able to boot your machine in some other way, set
the CD-ROM's blocksize with a devscsi program while the system is up
and then install from it, but I won't swear to it. Late R4K Indigos,
Indys, Indigo2s, and Onyx/Challenges all know how to set the block size
if the drive identifies itself as a CD-ROM, reports the block size as
something other than 512 bytes in the block descriptor and accepts the
new block size in the block descriptor.

Rob Silvers <[email-masked]> reports that he has been sucessfully
using a third-party dealer's Toshiba TXM3401E1 on an Indigo. It cost
about $760. It is physically larger than an external Apple or Next
drive. It is double speed and handles multi-session photo-CDs.
'cdromd', 'inst' and 'cdman' work, but he has not tried to boot from it
as of 12 June 93.

Bart Richards of Thunderstone Software <[email-masked]> writes,
The following minor surgery makes a run of the mill Toshiba 3401[B|E]
CDROM drive SGI [Indigo] or Sun-compatible. I got it straight from an
anonymous Toshiba Tech. guy, and it worked for me.

There are two solder pads located on the circuit board at the back
right corner of the drive's aluminum housing when viewed from the top
with the SCSI connector facing away from you. These may or may not be
labeled as '0' & '1', but '0' is on the left and '1' is on the right
(or closest to the edge of the circuit board).  The normal state for
these solder pads from the factory is for both of them to be closed.

With an Exacto Knife or soldering iron (whichever is appropriate for
the desired configuration), cut or solder these pads to match the
entries in the following table:

                                                +++___++++++++__
                                               |power   SCSI    |
'0'   '1'  O=CUT/OPEN S=SHORTED/SOLDERED       |              01|
----------                                     |----------------|
 S     S   Toshiba Default (2048 byte block)   |                |
 S     O   512 byte blocks                     |     TOP        |
 O     S   SGI ( Bootable )                    |     OF         |
 O     O   Sun / Integraph                     |     DRIVE      |
                                               |                |
                                               |                |
                                               |                |
                                               |________________|
                                                      DOOR

------------------------------

Subject:   -35- Why can't Joe User eject his CD-ROM?
Date: 24 Feb 94 00:00:01 EST

- /usr/sbin/eject has the wrong permissions in IRIX 4.0.5H and IOP. It
  should be setuid root. Say 'chmod 4755 /usr/sbin/eject' (as root) to
  fix it.

- Someone may be cd'ed into the CDROM directory. Do 'fuser /CDROM' to
  find the number(s) of the process(es) that are cd'ed there, and kill
  them.

------------------------------

Subject:   -36- How can Joe User mount and unmount his MO disk?
Date: 22 Jan 94 00:00:01 EST

cdromd (mediad in IRIX 5.x) doesn't understand MO disks. You need the
'mountmo' program, at viz.tamu.edu:/pub/sgi/hardware/mountmo.c.

------------------------------

Subject:   -37- Why do SGI SCSI controllers have host ID 0 instead of
                the usual 7?
Date: 24 Feb 94 00:00:01 EST

It's a controller chip default. It was left alone because it doesn't
matter much: host ID doesn't affect throughput, except perhaps on a
horrendously overloaded bus. However, drives whose ID is set by jumpers
are usually shipped with ID 7 (all three jumpers on), so you can just
plug one in to an ID 0 host.

------------------------------

Subject:   -38- EVERYTHING ELSE
Date: 09 Jan 94 00:00:01 EST

The rest of the FAQ discusses things that didn't fit into categories.

------------------------------

Subject:   -39- How long can my monitor/keyboard/mouse cables be?
Date: 25 Feb 94 00:00:01 EST

Dave Olson <[email-masked]> writes,
SGI has (or had at one time) a 75 foot monitor cable on the price
list.  With a decent cable, this is about as far as you can get without
getting pretty fuzzy; I've heard that with an extremely high quality
cable, you can get to about 100 feet.  Your limits may vary.  EIA 423
should have no problems with up to 100 feet either, since the mouse is
at 4800 baud, and the keyboard at 600.

Will McCown <[email-masked]> adds,
We routinely extend the SGI video cables up to about 150' using high-
quality (Canare LV-61s) coaxial cables.  For newer SGIs which use the
13W3 "D" connector instead of BNCs, adapters are available from several
sources including NuData (908) 842-5757 part number 6647.

The "PS/2 compatible" keyboards and mice used on the Indigo II, Indy,
etc. do not accept simple extension cords as well as the older
keyboard/mice.  We have successfully extended these keyboards & mice up
to about 100', but beyond 150' they never work.  The problem lies in
the high-impedance TTL-level signaling used.  Beyond this distance you
can use an extender box made by Cybex (205) 430-4000, which is designed
to extend the IBM PS/2 keyboard and mouse.

Our method for making keyboard/mouse extensions is to buy 6' IBM PS/2
keyboard extension cables (male 6-pin mini-din one end, female 6-pin
mini-din on the other), and cut the connectors off of these cables
leaving about a 6-12" pigtail on each connector.  We then attach RJ-12
connectors (IDC type modular phone connectors) to the free end of each
pigtail.  We then extend the cable using flat 6-conductor phone cable,
RJ-12 connectors, and "barrel" adapters.  This may sound like a lot of
work but it is very quick to assemble, and requires no soldering.

For really long runs, Rick McLeod <[email-masked]> says,
Two companies provide long distance (up to a couple of thousand feet)
fiber optics extensions for keyboard, mouse and monitor:

    Lightwave Communications		(203) 878-9838
    Meret Optical Communications	(310) 828-7496

------------------------------

Subject:   -40- What is "/dev/tport" used for?
Date: 26 May 93 00:00:01 CST

Mark Stadler ([email-masked]) says:
/dev/tport is a streams based tty device driver which can be in one of
2 modes:

- when X is not running, /dev/tport gets its input from the graphics
  keyboard and images in the frame buffer (textport mode).  This mode
  is only intended to be used in single-user mode or during
  transitional periods when the X server is not running.

- when X is running, /dev/tport doesn't get any input and generates no
  output.  Any programs or shells using /dev/tport hang on reads and
  toss writes.

Kind of a strange device.  But it makes more sense with a clear
understanding of how /dev/console works.

/dev/console is kind of like a terminal switch box.  Rather than
switching physical rs232 cables, we direct console output onto the
output stream of other streams-based devices who request such behavior
with TIOCCONS ioctl.

By default, /dev/console directs its output to /dev/tport.  In the
absence of a windowing system this causes console output (including
kernel prints) to show up on the textport in front of you.

Once the window system is started, the /dev/tport is no longer
visible.  Thus the console is no longer visible.  At this point, a
terminal emulation window (using streams based ttys) can issue the
TIOCCONS ioctl to cause console output (including kernel printfs) to
show up in the emulation in the window in front of you.

Note that when you bring the window system down, /dev/tport is still
there with the same session it started with and the console output
redirected back to it again.

------------------------------

Subject:   -41- How fast is the Indigo parallel port?
Date: 26 May 93 00:00:01 CST

Default rate is about 200Kbytes/sec.  This can be bumped up to at least
400, and perhaps higher by changing the strobe length, assuming the
other side can handshake fast enough.  See the plp(7) manpage.

------------------------------

Subject:   -42- What are the differences between the Indigo R4000 and
                Indigo2?
Date: 9 Jun 93 

Jamie Riotto <[email-masked]> writes:

An Indigo R4000 has two daughter board expansions which use our
GIO-32BIS bus design. These cards are about the size of an index card.

An Indigo2 has a 4-slot backplane design. All four slots have EISA
connectors so you can have a graphics-less server with four EISA cards.
Three of the slots have GIO-64 bus connectors, BUT ONLY TWO CONNECTORS
CAN BE USED SIMULTANEOUSLY!. Graphics board sets take up one logical
GIO-64 connection, but can take up more physical slots. The current
Extreme graphics takes up one logical GIO-64 connection, but uses three
slots. That means the other slot can be used for either EISA or GIO-64
expansion. Note that since not all slots have both EISA and GIO-64
connectors, you might have to shift the Extreme graphics board set up
or down a slot if you want to use the fourth slot with GIO-64
expansion.

GIO-64 by the way is similar to GIO-32 but is twice as wide, uses a
different DMA protocol (pipelined), and used EISA form factor (with the
connector moved of course :-).

------------------------------

Subject:   -43- What high speed interfaces are available for Onyx?
Date: 11 Jun 93 

Robert van Liere <[email-masked]> writes:
SGI have FDDI boards for the Onyx. These boards perform quite well
although the Indigo FDDI broad preforms slightly better. I'm not sure
about SGI ATM, although I guess all vendors are preparing for it.

FORE systems make ATM boards for the GIO bus. Maybe they have something
for the HIO as well.

		FORE systems, Inc
		1000 Gamma Drive
		Pittsburgh, PA 15238-2940
		412-967-4040
		Fax 412-967-4044
		[email-masked]

		GIA-100/125A	(100 Mbps GIO Bus)
		GIA-100/175A	(140 Mbps GIO Bus)
		
and Yechezkal-Shimon Gutfreund <[email-masked]> adds:

Fore Systems, Pittsburgh PA, selles a 150Mbit/s ATM adapter card that
you can use to connect to their ATM switch (using multi-mode fiber).

------------------------------

Subject:   -44- Why doesn't my modem work?
Date: 10 Dec 93 00:00:01 CST

Lots of reasons, but here are three of the most popular:

- You're not using hardware flow control. To do so, you MUST 1) use the
  ttyf* devices, not ttyd* or ttym*, and 2) use a "hardware handshake"
  7-wire cable, which you can buy from SGI but usually *not* from a
  Macintosh house. Look at the serial(7) manpage for details.

- The modem is configured funny. Look at the configuration scripts in
  /usr/lib/uucp/fix-* and see if there's one for your modem.

- /usr/lib/uucp/Permissions is wrong. /usr/lib/uucp/genperm will
  generate Permissions entries for all /usr/lib/uucp/Systems entries.

------------------------------

Subject:   -45- What mice can I use with my Indigo or Indigo2?
Date: 09 Jan 94 00:00:01 EST

Indigos need special Indigo mice. Replacement mechanical or optical
(take note, mechanical mice haters!) mice are available from SGI or
directly from Mouse Systems (510-656-1117).

Indigo2s can use PS/2 mice as per the pcmouse(7) manpage. Dave Yost
expands on this:  The Indigo2 takes any industry standard mouse of the
variety variously known as "IBM PS/2", "Mouse Port" or "6-pin".  A PC
serial mouse won't do, even with an adaptor, unless it is claimed to
work on a PS/2 through an adaptor.  The Logitech "MouseMan Cordless"
mouse works for me.

------------------------------

Subject:   -46- What about uninterruptable power supplies?
Date: 12 Feb 94 00:00:01 EST

See the misc FAQ for a pointer to the UPS faq.

------------------------------

End of sgi/faq/hardware Digest
******************************