SGI: Hardware

So uunix and I scored a good price on a brace of Indigo's (R4000 100MHz, 128MB RAM, XZ Graphics) and we're going to be taking one each.

I took to tinkering with mine last night and ran into some interesting quirks.

Firstly with no HDD installed in the internal slots, the system won't get to the prom. It powers on, makes the chime, and then just dumps some horrible kernel panic type error message that starts with an: 'Exception: <vector=UTLB Miss>'

Even if I have an external drive plugged into the external SCSI port, it throws the same error. Without an internal disk plugged in, it's not happy. As soon as I have a legit disk installed internally, it'll come up to the PROM OK.

Secondly. Compatibility of disks for the internal slots. A number of disks which I would have expected to work just sit and endlessly make a weird, weak half powering up type noise but... never actually spin up. The prom eventually comes up after a small delay, and doesn't find the disk. I eventually managed to find a single drive which would actually work and power up (old 4GB Seagate jobbie) - several others just made this same weird noise.

Thirdly.. I put in a 15,000RPM drive connected via a 50pin to 80pin SCSI convertor (which works just fine in my Indigo2 and my Indy) and the system won't even switch on... is a 15K drive too much for the PSU in the Indigo?

I did try searching but information on Indigo's seems a little thin unfortunately!

chicaneuk wrote: Firstly with no HDD installed in the internal slots, the system won't get to the prom. It powers on, makes the chime, and then just dumps some horrible kernel panic type error message that starts with an: 'Exception: <vector=UTLB Miss>'

Unfortunately that's a sign there's something very wrong with your Indigo. It should get you to the PROM just fine. With the disk pulled from mine, I get the following on the console:

Pressing any key takes me to the usual PROM menu. (And it works the same with either a serial console or a directly attached monitor/keyboard.)

The other symptoms make me wonder if your power supply is marginal. Or maybe there's a problem with the SCSI cabling/backplane. Or the host-side of the SCSI bus. Or ...? Sorry I can't offer much help on the diagnosis of the problem. All I can say is that you should get to the PROM menu even without a disk installed. Yours seems to be failing very early, while running the internal diagnostics. (In which case, maybe try re-seating the RAM and the CPU module?)

http://www.gossamer-threads.com/lists/gentoo/mips/58109

It does look like a boot disk issue of some type. Do they have terminators on SCSI port on the back? Not sure if required, I saw a pic of an Indigo the other day and it had a SCSI terminator.

It could need a bit of reseating, since the seller had taken pics of the HINV.

Doesn't seem to be the same issue uunix - my similar sounding error message occurs without even going near loading anything off a disk. Once it has a disk in that it's happy with, it will come up to the PROM fine and seems to boot into 'fx' or the IRIX installer OK. The external SCSI port does indeed have a terminator on it.

Looks like I'll have to try crack it open and reseat everything just to rule that out. I won't lose too much sleep if there's something wrong with it as it wasn't an expensive acquisition but would be nice to know it's in good health!

I'd look at the power supply. Base check - try to get a second sled and look at voltage levels with a drive and boards in place. Better check - look at it with a scope to see if there's funny waveforms riding on there that shouldn't be there.

Officially all SGIs should have a terminator on the external SCSI port per SCSI specs. Unofficially they usually work just fine without one, especially if it's a single disk (the inside end of the bus is terminated).

Sadly multimeters and oscilloscopes are not something I've ever owned or been familiar with - not an electronics guy at all

Check the power supply from the other system to rule it out?

uunix wrote: Check the power supply from the other system to rule it out?

I suppose you could swap them, however keep in mind that every time you take the machine apart you run the risk of something happening. I was thinking plug a meter in a spare sled and check the +5V (especially) and +12V while you have boards and disk in the machine. The fact that several drives have not spun up is suspicious, and if there isn't enough power on the +5V rail to run the logic strange things can happen on the SCSI bus. Try the disks that don't work in the other Indigo and see if they come up there. (note- some disks wait for a spin-up command, and if it never gets there the drive won't come on, so check the jumpers and make sure it isn't set that way). Some wide disks don't autonegotiate narrow mode properly with SGIs either, so go ahead and force it single-ended/narrow just to make sure (assuming it's a 80-pin SCA drive, which is probably the best type to use as they're usually much newer).

I have had failing disks give that error, and it could be worthwhile to re-seat the IP20/HP2 board and include a few well placed taps with a rubber/plastic mallet (that has fixed several odd bus errors on VME Suns that I've come across).

I tried the power supply from the other system and the behaviour is the same.

I reseated the main and graphics boards and again, no change. At this point the system is happily booting IRIX 6.2 with the only disk I did manage to get working, so I'm fairly reluctant to start pulling anything else further apart so have just reassembled it and shelved it. I guess my Indigo has got some.. um.. quirks which I'll just have to live with!

Have you tried my machine with no disks in?

I haven't mate. Packed all the kit away again as the spare room will be getting used as a bedroom over the weekend, but will try remember to fire yours up minus disks and see what happens next week!

OK, I'm sure we will sort it when I get over there

chicaneuk wrote: Sadly multimeters and oscilloscopes are not something I've ever owned or been familiar with - not an electronics guy at all

If you're going to get one or the other, don't be misled by the apparent "complexity" of an oscilloscope. In general they are really easy to use and tell you much more about what's going on than a meter. And the current craze for digital meters can be wrong-headed. Inexpensive digitals can't even see fast-moving changes.

Simple example : you check the voltage of your power supply. Digital meter tells you 4.93 volts. Cool, within spec ! Oscilloscope shows a base of 4.93 volts but more noise than the dining hall of a Chinese university. You need new caps !

An inexpensive 20 mhz one would probably be fine for anything you're likely to do. Just don't pick up one of those thirty-ton antique Tektronix thingies for $5 at the surplus store ... they look cool but not worth the hassle. You want small and light.

hamei wrote:

chicaneuk wrote: Sadly multimeters and oscilloscopes are not something I've ever owned or been familiar with - not an electronics guy at all

If you're going to get one or the other, don't be misled by the apparent "complexity" of an oscilloscope. In general they are really easy to use and tell you much more about what's going on than a meter. And the current craze for digital meters can be wrong-headed. Inexpensive digitals can't even see fast-moving changes.

Simple example : you check the voltage of your power supply. Digital meter tells you 4.93 volts. Cool, within spec ! Oscilloscope shows a base of 4.93 volts but more noise than the dining hall of a Chinese university. You need new caps !

An inexpensive 20 mhz one would probably be fine for anything you're likely to do. Just don't pick up one of those thirty-ton antique Tektronix thingies for $5 at the surplus store ... they look cool but not worth the hassle. You want small and light.

I'd go in the following order: Decent DMM (Fluke 70 series is a good general purpose unit), scope, analog meter (VTVM if you can). DSOs are sweet - once you get one you'll wonder how you managed with an analog. Downside: my LeCroy (pre-Windows) doesn't do X-Y mode . Don't know about them new fangled LCD thingies, guess they might. Actually can't remember about my Tek analog storage unit either. Troll surplus lists and used postings, scopes have always been expensive new.

Hi

I don't have much to add, but... I brought my old Indigo back to life today with a new TOD battery (I've replaced it before with a Tadiran cell, which also ran out and now I have a CR2032 in there).

Anyway. I have several sleds and drives and while trying to find a bootable system I started the machine without disk and got the same symptoms. I do recall starting the machine diskless before without problems. A terminator on the external port doesn’t make a difference.

Here is the full error message for future reference:


I've copied it by hand since I don't have a serial connection handy.

Ok, now I have something to add.

I tried moving memory arround to no avail. I have a space CPU board with a bad TOD clock battery so I swapped CPU modules, no change.

Then it dawned on me, I have a funky little SCSI floppy drive in the top slot which I put in the machine some time ago but never tested.. Removing the floppy drive "cured" the problem. The only conclusion I can draw is that, at least in my case, there is something funny going on with the SCSI bus when the floppy drive is alone in the SCSI-chain. I'm looking at the hinv now and both the drive and floppy is identified.

Glad to know that mine isn't alone in it's weirdness though I must admit I haven't tinkered with it since making the post. Pretty sure I don't have any other drives on mine (floppy or whatever) and like you had terminated the SCSI, but I think the CR2302 battery on mine has died since so doesn't really want to play anyway.

Will have to have another evening fighting with it - see if I can get it to behave.

I had a disk go on mine also and the floppy does cause issues when it's attached. My battery had been fixed with a CR2302, but required a redesigned hairclip to enhance the connections.

The problem with mine is that the mouse goes haywire randomly. Not after a certain time or activity or anything etc.. It may work ok on boot up.. then again it may not, it may work after 10 mins, then again it may fail after 10 mins.. Anyway, it's in the loft for a later day.