--- Pete Turnbull <pete(a)dunnington.u-net.com> wrote:
> > Last I checked, 10base2 still has a distance advantage, perhaps enough
> > to matter for really large buildings.
>
> Yes, 185 metres instead of 100m -- and 10base5 will go to 500m. But you
> can do better and faster with fibre.
I've already got fibre - a pair of StarLAN 10Base-T to 10Base-FL media
converters (old and huge, but they work) and a pair of more modern
10Base-FL transceivers. I have a single fibre pair run up the walls
>from the basement to the computer room on the second floor and my eventual
goal is to lay fibre between my farmhouse and my quonset hut.
I even have _one_ fiber long-haul modem - it looks like a DB25 - RJ11/RJ45
shell, but has one ST connector on it. Over a single fiber it multiplexes
a full duplex 9600 baud signal and a second full duplex 1200 baud signal that
can be used for flow control or an additional, low-speed channel. A friend
of mine has its mate and if he ever finds it, I'll probably use it to monitor
some console port on a PDP-11 in the quonset hut. Maybe I'll build a 20Ma
to RS-232 converter and run an ASR-33 over it. :-)
But I still want a piece of thicknet on my network, just for the amusement
value. The fibre is for "gee whiz" value.
-ethan
=====
Even though my old e-mail address is no longer going to
vanish, please note my new public address: erd(a)iname.com
The original webpage address is still going away. The
permanent home is: http://penguincentral.com/
See http://ohio.voyager.net/ for details.
__________________________________________________
Do You Yahoo!?
Yahoo! Shopping - Thousands of Stores. Millions of Products.
http://shopping.yahoo.com/
Don't forget the oric 1 and atmos, Amstrad cpc and the MSX representatives
and other "WOW L@@K Spectrum Era" types of computers.
I though Air France was going to fix the Concorde... Then forget it I don't
want these computers to end up in a hotel in some big city's suburb.
Francois
>
>All we have to do is wait for British Airways to get the
>Concorde fixed, and stuff it full of BBC micros,
>Whitechapel workstations, Acorn Atoms, Tangerines, Dragon
>32s, UK101s and transputers.
>
>:-) :-)
>
>--
>John Honniball
>Email: John.Honniball(a)uwe.ac.uk
>University of the West of England
>
In a message dated 11/21/00 3:12:15 AM Eastern Standard Time, red(a)bears.org
writes:
> One more thing, I believe that Linux has loadable filesystem module
> support for EFS, which would be the filesystem used by these systems. I
> can't say whether this is read/write support or simply read-only, but it
> might be worth investigating. I don't make a point of staying abreast on
> what's new and improved with Linux.
>
I am going to try that as soon as I have a spare few minutes. I knew Linux
supported EFS but wasn't sure which file system type this old SGI had. As
far as I know the Linus EFS support is read only, so I'll have to grab the
password file and run John the Ripper on it in hopes of a breakthrough I
guess. As far as Linux goes, I have to stay abreast of changes since I am on
of the co-founder's of the Lehigh Valley Linux User Group.
-Linc Fessenden
http://members.aol.com/lfessen106 (Computer Collection)
http://thelinuxlink.net/lvlinux (LVLUG)
On Nov 19, 22:18, Tarsi wrote:
> >Yes, 185 metres instead of 100m -- and 10base5 will go to 500m. But you
> >can do better and faster with fibre.
>
> Well, wouldn't we ALL like fiber, but I just don't think it's in my
budget. :)
Not really in mine either, but I have a few bits of cast off FOIRL and long
patch leads that were discarded (wrong connectors for the more modern kit).
Anyway, since most of my machines are within 50m of each other, and few can
manage 100MB let alone more, there's little point in buying fibre for my
home systems :-)
--
Pete Peter Turnbull
Dept. of Computer Science
University of York
On Nov 20, 20:35, LFessen106(a)aol.com wrote:
> They both have the PS2 KB port.. I tried an actual PS2 KB, it lit up as
> expected, but I got a no console error.. Do you think it will actually
use a
> PS2 KB and just needs to detect a mouse as well (with a PS2 splitter) or
the
> SGI PS2 KB/Mouse is proprietary? I did read somewhere that some SGI's
use a
> standard PS2 KB...
Indy, Indigo^2, O2, etc use a PS/2 keyboard (or a PC-AT keyboard with a DIN
to miniDIN adaptor) and PS/2 mouse, running at +5 volts. All the earlier
machines use one of several variants of a proprietary protocol/pinout,
basically RS423 running at +/- 8 volts or more.
>From the manual page:
The pin assignments for the DIN-6 keyboard connector on the CPU board
of
some of the newer systems are shown in the following table:
___________________________________
|_____KEYBOARD_CABLE_PINOUT_______|
|Pin | Signal | Description |
|____|________|___________________|
| 1 | KRCD | Keyboard Receive |
| 2 | MRCD | Mouse Receive |
| 3 | GND | Ground |
| 4 | +8Vdc | Power |
| 5 | KTXD | Keyboard Transmit |
|_6__|_-8Vdc__|_Power_____________|
For machines whose keyboards have the DIN-6 connector on the keyboard,
as well as on the CPU, the pinout is shown in the following table.
The
connectors on both sides of the keyboard have identical pinout, either
may be used for the mouse and the cable to the CPU.
__________________________________
| KEYBOARD CONNECTOR PINOUT |
|_________________________________|
|Pin_|_Signal_|_Description_______|
| 1 | KTXD | Keyboard Transmit |
| 2 | MTXD | Mouse Transmit |
| 3 | GND | Ground |
| 4 | +8Vdc | Power |
| 5 | KRCD | Keyboard Receive |
| 6 | NC | Not Connected |
|____|________|___________________|
The interface between the keyboard and the system is 600 baud
asynchronous. The format used is one start bit followed by eight data
bits, an odd parity bit and one stop bit, with one byte sent per key
up
or down transition. The MSB of the byte is a "0" for a downstroke and
a
"1" for an upstroke. Control bytes are sent to the keyboard with the
same speed and format. The system software does all the processing
needed to support functions such as capitalization, control
characters,
and numeric lock. Auto-repeat for a specified set of characters can
be
turned on or off by the system software by sending a control byte to
the
keyboard. When auto-repeat is enabled a pressed key will begin auto-
repeating after 0.65 seconds and repeat 28 times per second. The
keyboard initializes upon power-up. The configuration request control
byte causes the keyboard to send a two-byte sequence to the system.
The
second byte contains the eight-bit value set on a DIP switch in the
keyboard. All keyboard lights (if any; some newer systems have
keyboards
without user controllable lights) are controlled by the system
software
by sending control bytes to the keyboard to turn them on or off.
Control
bytes are also used for long and short beep control and key click
disable.
For the mouse:
Signals: The serial data interface signal level is compatible with
RS-423
which has roughly a 10V swing centered about ground. The idle state
and
true data bits for the interface are Mark level or -5V whereas false
data
bits and the start bit are spaces or +5V. The serial data is
transmitted
at 4800 baud with one start bit, eight data bits, and no parity.
Protocol: The mouse provides a five-byte data block whenever there is
a
change of position or button state. The first byte is a sync byte
which
has its upper five bits set to 10000 and its lower three bits
indicating
the button states where a 0 indicates depression. The sync byte looks
like this: 10000LMR. The next four bytes contain two difference
updates
of the mouse's change in position: X1, Y1, X2, and Y2. Positive
values
indicate movement to the right or upward. System software ignores
bytes
beyond the first five until reception of the next sync byte.
--
Pete Peter Turnbull
Dept. of Computer Science
University of York
In a message dated Mon, 20 Nov 2000 2:52:29 PM Eastern Standard Time, Mark
Green <mark(a)cs.ualberta.ca> writes:
<<I would strongly advice getting the console working. The monitor
part is easy, most VGA monitors will work. Depending on the graphics
option that's installed in your machine you should have either a
VGA or BNC connectors (some of the later graphics options used
13W3 connectors). I've had success with a wide range of monitors.
The standard resolution is 1280x1024 I believe (they came standard
with 19 and 21 inch monitors), but I've used 1025x768 monitors, a
bit fuzzy, but it works.>>
Yes, I got a monitor hooked up to it without prblms. I have both SVGA's that
will handle it and also a few RGB's that'll take care of it as well.
<<The keyboard and mouse is much harder. There were several models
of keyboards used on these machines. What type of keyboard
connector to you have? The popular ones were DB9 and PS/2 (note
I don't think a PS/2 keyboard will work, but I haven't tried).>>
They both have the PS2 KB port.. I tried an actual PS2 KB, it lit up as
expected, but I got a no console error.. Do you think it will actually use a
PS2 KB and just needs to detect a mouse as well (with a PS2 splitter) or the
SGI PS2 KB/Mouse is proprietary? I did read somewhere that some SGI's use a
standard PS2 KB...
<<I can look up the part number tonight when I get home. The keyboards
are not that common, but I have seen them on eBay. The mouse attaches
to the keyboard.>>>
I would really appreciate that.
<<The easiest way to get these machines running is through the
console. There is a way to set a terminal to be the console,
but I'm not sure how its done on the PI. On some SGIs there is
a hardware mechanism, but on others the console must be use (this
won't help you much).>>
I can get the console through a dumb terminal easily by using a regular modem
cable (NOT null) on serial port 1. Works like a charm, but no lovely grfx..
<<Its difficult to do much without a console, since all the installation
and maintenance procedures assume that you are working through the
console by default. What devices do you have? There are two forms
of the OS media. The older systems were on tape, and the newer ones
were on CD. A may have IRIX 4 tapes at home, which could get you
started. The 4D/35 will run up to IRIX 5.3 (something I recommend),
and the CDs can be found regularly on eBay. Note that these machines
are a bit picky about the CDROM drives they use, older ones are
better.>>
I would be eternally gratefull for somekind of media. There are no tape
drives on these things at all - they both have 2 scsi drives and a scsi
floppy installed. The only OS info I can find is that the one runs Irix 4.0.
(5 or 2 can't remember). I do (of course) have an external scsi cdrom (works
on a sun) and a couple external DAT drives that I bet would work on teh SGI's.
<<It sounds like the previous owner on your second machine wiped
the disk. The lack of a disk label is a good indication that there
is nothing on the disk.>>
Unfortunately I think you're right.
<<Do you have access to any of the accounts on the first machine?
Quite often the guest account had no password, so you could
try that. If you are successful, run hinv to get your machine's
configuration.>>
Tried 'em all - Nope..
<<If you have a console the easiest way to change the root password
is to boot a mini-root (this may be on partition 8 of your disk).
>From there you can modify the /etc/passwd file.>>
How would I go about doing this?
<<SGI tended to use there own file system structures, so you may
not be able to read the disks on other UNIX systems.
Let me know if this helps you. My machines are at home, so I
can provide any detail until tonight. One word of warning the
4D/30 series machines had a habit of catching fire. The CPU
used in the 4D/30 machines generated much more heat than the
4D/20 machines, and the cabinet really wasn't designed for them
The upgrade included an extra fan. If any of the fans fail the
system overheats. Also run with all the skins on for better
heat flow. One of the 4D/35s I had a work caught fire one
day, filled the room with smoke.
>>
Thanks for all your help Mark, I appreciate it!
-Linc Fessenden
In a message dated Mon, 20 Nov 2000 3:48:10 PM Eastern Standard Time, Corda
Albert J DLVA <CordaAJ(a)nswc.navy.mil> writes:
<< I've played with a number of SGIs over my career, both at home
and at work. I put up a web page a while ago with most of the info I've
gleaned ("This Old SGI", http://www.geocities.com/SiliconValley/Pines/2258)
Unfortunately, the web page is woefully out of date as I haven't
had time to go back and restructure it the way I'd like.>>
I love that site - it's the one that provided nearly all the info I have on
these up to this point!
<<Just as in the comments below, I recommend going with Irix 5.3. It will
run reasonably on this machine (with sufficient memory), and provide quite
a bit of functionality.>>
Anyone interested in helping me with *inexpensive* media for these?
<<One thing I _strongly_ recommend... Use an air gun (or canned air) to blow
out the dust throughout the entire case (including air plenums, power
supply and e-module(where the circuit cards are)). I disassembled mine
(including removing the power supply and popping it cover) to clean it.
This critter acts just like a vacuum cleaner and will suck dust and dirt
up from the bottom airgrate faster than you can imagine. At work, we
mounted these things on small (6") pedestals to try to cut down the
amount of internal dust they sucked up. I imagine the accumulated dust
might contribute to the fire problems mentioned below.>>
After opening the cases I noticed that these suck dirt better than a
hoover!!..
<<...Good Luck!...
-al->>
Thanks for all the info Al!
-Linc.
On Nov 20, 12:47, Mark Green wrote:
> The keyboard and mouse is much harder. There were several models
> of keyboards used on these machines. What type of keyboard
> connector to you have? The popular ones were DB9 and PS/2 (note
> I don't think a PS/2 keyboard will work, but I haven't tried).
> I can look up the part number tonight when I get home. The keyboards
> are not that common, but I have seen them on eBay. The mouse attaches
> to the keyboard.
I haven't checked thoroughly, but I'm fairly sure all the keyboards use the
same protocol (a serial protocol, 600 baud IIRC), just different plugs.
The 4DFAQ (aka "This Old SGI" -- try a web search) is helpful about this
sort of stuff.
> The easiest way to get these machines running is through the
> console. There is a way to set a terminal to be the console,
> but I'm not sure how its done on the PI. On some SGIs there is
> a hardware mechanism, but on others the console must be use (this
> won't help you much).
I thought all the PIs use the first serial line automatically if the
keyboard isn't connected?
> > 1 of them still has a working OS, and the other doesn't. I do not have
any
> > OS media for them at all, and the one that IS working has (Of Course) a
root
> > password which I do not have. What I really need here is a copy of the
> > installation media here. Pleeeaaaasssee Contact me if you can assist
in
> > getting these systems running. I believe the 1 with the OS problem has
the
> > OS, but has no scsi disk label. Perhaps if someone were to have a
root/boot
> > disk they could copy off for me, I could get them working. I believe
they
> > run Iris 4.0.somthingorother.
> >
>
> Its difficult to do much without a console, since all the installation
> and maintenance procedures assume that you are working through the
> console by default. What devices do you have? There are two forms
> of the OS media. The older systems were on tape, and the newer ones
> were on CD. A may have IRIX 4 tapes at home, which could get you
> started. The 4D/35 will run up to IRIX 5.3 (something I recommend),
> and the CDs can be found regularly on eBay. Note that these machines
> are a bit picky about the CDROM drives they use, older ones are
> better.
I agree; definitely get 5.3 if you can. It does take more disk space,
though.
> If you have a console the easiest way to change the root password
> is to boot a mini-root (this may be on partition 8 of your disk).
> >From there you can modify the /etc/passwd file.
If you can't get to that, because there's a password set in the NVRAM, so
you can't get to the PROM monitor, the FAQ describes one way to defeat the
NVRAM password.
> SGI tended to use there own file system structures, so you may
> not be able to read the disks on other UNIX systems.
Did 4.0.5 etc use EFS? 5.3 does, and Linux can mount/read that.
> PS: Are there other SGI collectors on the list?
Yes, but most of mine are later than these -- three Indigos, two Indys, and
an Indigo^2.
--
Pete Peter Turnbull
Dept. of Computer Science
University of York
On Nov 20, 13:17, Ethan Dicks wrote:
> But does anyone out there use Thicknet at home?
Is there another kind? :-)
> I have one vampire tap
> transceiver (and a bunch of 10Base2). I would love to set up a segment
> of 10Base5 just for the historical sake of it all. I suppose I would
> need at least one more 10Base5 transceiver to make it worthwhile.
I've got a bit of most common types at home. Well, thick (with nice long
blue drops to complement the thick yellow coax), thin, and UTP, anyway.
And a few feet of FOIRL too.
--
Pete Peter Turnbull
Dept. of Computer Science
University of York
