The collected works of Black Cardinal - Page 1

Cool! It looks to be in good shape, too. From the pictures it looks like it didn't come with a hard drive. Are you going to put a drive in it and install HP-UX?

I have a soft spot in my heart for HP 715 and 712 PA-RISC workstations. I spent a lot of time in graduate school on a 715/100 named 'kilovolt' and when I couldn't get that machine I was on a 712/80 named 'penstock.'

I was actually shopping for a 715-series workstation out of nostalgia but after some research I decided to get an Indigo2 instead, even though I never used SGIs that much in school. Wife Acceptance Factor and kids limit how many boxes I can keep around, so I went for something a bit more exotic to represent Unix in our household.

Your problem is different than mine was but I recently fixed a problem with my MaxImpact that I originally suspected to be TRAMs. It turned out to be main memory instead. My symptom was corrupted textures in a few applications (SkyRocket and distort). Reseating all of the DIMMs fixed the problem (I actually re-arranged them, too). Results from internal diagnostics is what led me to suspect the DIMMs.

Anyway, as I said your problem is different but if your diagnostics report main board errors then it could be something apparently unrelated like main memory.

I thought that Harvard Graphics was the de-facto standard for presentation software before PowerPoint. Did the Aldus package run on PCs too, or just Macs?

Excel took over from Lotus 1-2-3 because the mouse-driven interface and WYSIWYG editing made it much easier to use. It's a rare example of Microsoft actually developing a superior original product.

Quattro Pro competed for a while because it had similar advantages but I think it's the one that suffered more directly from the bundling of Excel in Office.

Maybe so, but that wasn't my experience. When I first used Excel 2 in 1989 (under runtime Windows/286!) it was miles beyond text-mode 1-2-3 that used the "/" key for accessing keystroke menus. I don't think there was a graphical 1-2-3 yet, nor could it use a mouse. The WYSIWYG capability of 1-2-3 at that time was simply a print preview. All changes to the spreadsheet were done in text mode.

The calculation features weren't anything that 1-2-3 couldn't do, but it blew it away in the usability department. If Lotus had a graphical version, we didn't have it where I worked at the time.

We still exited to DOS to run WordPerfect, though!

I brought home a MIPS-based Cobalt Qube 2 I picked up at the local university surplus store today, and the first thing I did was try to connect it to my (already running) Indigo2 through its second serial port to monitor the Qube's console during boot. When I first tried to connect to the serial port on the Qube, there was a little spark. Recalling a similar recent event at work with an ungrounded embedded system's serial port, I figured that the Qube just wasn't grounded through its power supply and had floated to some unknown voltage and would be fine once the serial was connected.

Bad guess. To avoid the spark, I first unplugged the Qube's 12V input, plugged in the serial cable, then tried to plug in the Qube again. Right away, I hear a loud CRACK and the Indigo2 buzzes through its speakers and shuts off abruptly, the Qube's 12V plug is charred, and neither the Qube or the I2 would turn on anymore. Oh, crap.

I unplugged both and had dinner with the family. When I came back a half hour later, I plugged back in the I2 and it fired right up. I'm running full diagnostics now, and it seems fine, other than the second serial UART failing loopback. So that's damaged.

The Qube is dead, so I'm about to open it up and start checking it out. I'm an embedded systems EE, so I at least have a chance at repairing it, but this still sucks.

What the heck did I actually do? RS-232 is supposed to be shorts-tolerant (it's in the spec), so even if the pins were wrong it shouldn't bring down the two systems. I could see the Qube possibly not being fully compliant, but not the I2. Does the Qube have some funky serial port pinout that's totally nonstandard? I've used both of the I2's serial ports before without problems.

Do Indigo2 power supplies have resettable thermal and/or overcurrent protection? It seems like mine does. I couldn't find it in any documentation but I thought someone here might know for sure.

Also, does anyone know if the serial hardware on an IP28 is repairable, or am I down to only one serial port from now on with this CPU board? Here's where I hope to find a discrete serial UART chip, instead of it being embedded in an SGI ASIC.

Yes, the 12V power supply input on the Qube. It has a custom 3-pin DIN-style connector, and came with the original supply.

By shorts-tolerant, I meant that the RS-232 spec requires the ports themselves to be shorts-tolerant, so that if you accidentally connect two pins together that are not supposed to be, it won't work but it won't be damaged, either. I know this is true for the signal lines (TX, RX, CTS, etc.), but I'm not sure about the power lines.

But even so, I find it hard to believe that Cobalt would have a special pinout for the DB-9 serial connector. And it is labeled "Serial," and from what I've read the only console it has is through its serial port.


The only PC around here is my wife's laptop, and I don't think she'd appreciate me using it to test my questionable hardware purchases! Seriously though, you have a good point.

I did test the Qube before I bought it, and it booted. It has a status LCD and I could see it doing a disk check. Here's a pic of the back of the Qube:

If so, that's scary. I'm only 38.

I did some troubleshooting on the Qube and discovered that a fuse had blown in the 12V brick power supply. It's a small 1.5A fuse soldered onto the PCB. I didn't have the correct (physical) size fuse, so I soldered in an inline AGC fuse holder for now. The Qube still wouldn't turn on, so I tried using an HP bench supply instead, but that didn't make a difference. Then I disassembled the Qube completely and put it back together one subsystem at a time, testing it under power, until I found the culprit: the hard drive. It's drawing considerably over 3A by itself and causing the power supply voltage to drop to about 4V. I don't know if the drive was already on its way out or if it died as a result of this episode. However, without the drive the Qube seems to power up OK with the brick supply again.

During the teardown I didn't find anything suspicious that might have caused a short. I tested the power supply to get the pinout, and verified that the Qube is isolated from the AC through its power supply, like a laptop. It's chassis is connected to the DC common, and SIGNAL GROUND on pin 5 of the serial port is tied directly to it as well. Even if the hard drive was shorting 12V to DC common, since the whole thing is floating relative to the AC it shouldn't have mattered when attached to the I2.

The I2 is not so good. It finished the diagnostic and although it only failed the loopback test for ttyd2, when I pressed ENTER to exit the diagnostic, the screen went black and it hanged. I shut it off, and now when I power it up it just reports " Warning: persistent break condition on serial port 0. " and then hangs. It doesn't even make it to the PROM maintenance menu. The next step is to crack open the case and take a look at what components are attached to the serial ports, I guess.

Wow, these are outstanding. I especially like how the Onyx2 includes the translucent sliding doors on the front. They should have made them black like your icon, that looks cool. It would have made more sense given the name, too.

I'll be looking forward to the Indigo2 R10K Impact version!

I took the Qube's hard drive (20GB parallel ATA) in to work today and tested it in a PC. It doesn't spin up at all, so it's either got a seized bearing and is drawing locked-rotor current or it has a short somewhere on its electronics. I'll try swapping in another disk this evening.

I'm also thinking about a clean way to ground the Qube's chassis instead of letting it float.

I'm anxious to get home to start troubleshooting the I2. I'm one of those people who can't stand being idle on a problem when there is clearly something I should be doing about it. I guess it's the engineering mentality.

Woohoo, I may be able to repair the Indigo2 after all! I was very happy to find a MAX249 serial interface chip on board:

This is a multi-channel serial port driver/receiver chip, one in a very popular line (the most famous version being the MAX232). It doesn't contain the UART itself, but converts from logic-level signals on the CPU/UART side to the +/-12V used in serial connections. The MAX249 version is a more sophisticated variant with enough channels to handle all of the data and control signals for at least two serial ports, and extra pins for readback of the values.

Here's the datasheet: http://datasheets.maxim-ic.com/en/ds/MAX220-MAX249.pdf

With a DMM I probed the chip and the DIN serial ports and found the following connections: (revised after I found a few errors in the MAX 249 pin names)

The second serial port has also very clearly been damaged. I'm not sure why I couldn't find a few of the pins on the MAX249. It's extremely unlikely they go anywhere else. Does the Indigo2 have ports that can switch between RS232 and RS422 like the Octane? If so, then there's probably another buffer chip to switch some of the connections around.

It's not a cheap chip at $20 from Mouser, but it's in stock and it's a PLCC so it's within my skills to remove and solder a new one in place. It's possible there was further damage beyond this one chip, but the fact that the only diagnostic that failed was the serial loopback test makes me hopeful that it was just unable to read back the values from the damaged MAX249.

If this doesn't solve the problem, as sybrfreq said I can always replace the IP28 board later.

That's what I was afraid of, thanks for the confirmation. man serial wasn't entirely clear on this.

I poked around some more with an LED flashlight and found two chips with visible damage:

The chip at the upper right is a SN75175, which is an RS-422/RS-485 driver/receiver. The one at the bottom right seems to be a DS4691M (the writing is partially obscured by bubbled plastic), and it's one of those obsolete chips that turn out a million search results in Chinese but none have a datasheet. From it's part number I suspect it's some sort of tri-state buffer chip used to switch between the MAX249 and the SN75175 for a few of the data lines. With a DMM I verified that both of these chips have several pins shorted to ground, and in the case of the DS4691M it even has one pin blown off! (The gap is not quite visible in the picture.)

The MAX249 may actually be fine, although in my experience PLCCs can be blown without visible damage, maybe because the package is so thick that the evidence stays buried under millimeters of plastic. The first thing I'll try is removing the two obviously damaged chips, and re-check the MAX249 for shorts to ground. If it's bad, too, then I'll replace it. I'm hoping that I'll be able to run the system with these two parts removed for now, and maybe replace them, or the entire IP28 board, later. If I'm really lucky I'll be able to use the second serial port as RS-232 even though the RS-422 hardware is gone.

I've removed the two visibly damaged chips and when I still measured low impedance between 5V and GND, I went ahead and removed the MAX249 as well. I also found a blown inductor on the I/O backplane board, which explains the missing connection for serial port 2's GND on pin 5:

However, the system still won't boot beyond the same error message as before: " Warning: persistent break condition on serial port 0. ". Any further troubleshooting will be very difficult, and it's not really worth it.

I guess I am now in the market for an IP28 board. I'll be posting in the Hardware Wanted section next. On the bright side, I have now been through a complete teardown and rebuild of an Indigo2. The hardest part is keeping your curious kids away from the myriad screws.

Due to a recent recent sad episode ( http://forums.nekochan.net/viewtopic.php?f=3&t=16723556&start=0 ) I need a new main board for my Indigo2 IMPACT. I'm looking for a working IP28 board, SGI part # 030-0978-002. I don't need RAM or a processor.

I would also consider another Indigo2 IMPACT with the correct board but would prefer just the main board to keep shipping low. Prefer U.S. or Canada for the same reason, although I will consider international if I need to.

I'm also looking for a "Fullhouse I/O backplane," the board with the PS/2, serial, printer, and AUI ports on it.

EDIT: I would also be interested in non-functional parts-donor Indigo2 main boards (IMPACT or not, any CPU version).

It looks like they didn't. According to a document on majix.org ( http://download.majix.org/sgi/ioc.pdf ), it should be a 176-pin part from VLSI. Fortunately, when I had the IP28 out I took some pictures of the board for later reference. There are no 176-pin parts on the board.

That document also includes a convenient list of the components used in the Fullhouse (Indigo2) design on page 22. I found the serial UART chip near the audio board, a Zilog Z8523010VSX. I'll do a little more probing to see if it might be damaged, too. This is an obsolete part, but as common as it was I can probably get hold of one somewhere.

Measuring with a ruler, my Multilink's DC plug is 2.5mm inside, 5.5mm outside. I'll have to see if I can find my calipers around somewhere to get a better measurement...

True, and I agree, but there is more paperwork when you ship internationally out of the U.S. The last time I did it, I had to fill out a longish-form to satisfy export requirements, and it's a pain. You have to look up ECCNs on a federal website. Even if it's no money out of the pocket of the seller, it is time.

What I don't understand is why our government requires all of this red tape for small shipments by individuals or small businesses.

Not the last time I shipped internationally, which was a few months ago. My local post office made me fill out a complete export declaration. I don't recall now where I was shipping to, but I think it was in Europe.

The Windows default calculator has different behavior depending on mode. In "Standard" mode, it ignores order of operations, and applies operators as you type. In "Scientific" mode, it follows standard order of operations rules. Try this:

2+3*4

It returns 20 in Standard mode and 14 in Scientific mode.

A good reason to keep a real RPN calculator nearby. You can trust the results.

Interlink (from MS-DOS 6.22) runs fine on older versions of DOS, and I think it even runs on a PC 5150. With an interlink/laplink cable (essentially a "null modem" for the parallel interface), it is much faster than using a serial cable.

Stoo, nice job on the Indigo2 images! Thanks!

Does an Onyx2 have an internal speaker? If so, where is it?

I didn't think it would but when running apps that use audio, certain sounds cause my Onyx2 to emit a nasty crackling noise. The workstation never emits any other sounds, such as boot chimes. (Other than fan noise, of course!) It doesn't matter if I have external speakers plugged in or not. External speakers do work properly with this machine.

Only certain clangy/crashy sounds do this, for example, when a tank is shot in bz or pretty much any sound when flying around in vroom . At first it sounded like electrical arcing but it seems more likely there's a ripped speaker cone somewhere in the chassis.

I thought someone here might know something before I tear the thing apart to find it.

Guess this is my month to ask SGI audio questions!

Hmm, OK. I'll do some troubleshooting before giving up on this PSU. Whatever the cause of the noise, it doesn't seem to be directly related to system load (i.e. current draw from the PSU). Running something CPU- and graphics-intensive like SkyRocket doesn't trigger the noise. So far, I have only observed that playing certain sounds correlates with it.

If it really is arcing, I'm surprised it's not causing other problems. Typically, a brief arc discharge causes a very large inductive spike that affects DC voltages throughout the system, not to mention a sudden voltage drop on the net that's arcing. But the system just keeps humming along.

Ryan, you said that you repaired one of these PSUs. Do you have any tips on troubleshooting it? Were you able to probe test points somewhere while it was running to look at the output voltages? Can the power supply be run on a bench by itself?

I had some time to work on this today. The sound is definitely coming from the IO6G, from a few cm behind the audio in/outs. I'm pretty sure it's coming from one of the relays in the picture below. For some reason, bz and vroom cause at least one of them to continuously toggle.

It's not just due to the sounds, either. I went into vroom 's data directory and tried playing the sound files directly using soundplayer and they play fine without making the noise.

Another clue may be that this machine can't record decent audio from the microphone port. It turns my voice into an 80s synthesizer with distortion cranked up to the max. I haven't tried the audio line in yet.

Any idea what these relays are for? I thought they might switch between the various audio ports, but the contacts don't seem to connect to any of them.

It's turning on & off rapidly. Here's a 5 sec audio clip I recorded of it while running vroom : (taken by my Indigo2)

http://www.gelhaus.net/irix/io6g_clicks.aiff

It's clearly not coming from the power supply, so my system isn't about to die an imminent death, but it's really annoying.


That sounds like a bad ball bearing in the power supply fan.

The relays are NEC/Tokin EB2-4.5NU miniature signal relays, and they have 4.5V DC coils and non-latching contacts. The datasheet was easy to find. I used very similar relays on a board at work a couple of years ago, and they sound exactly the same. People would come to my cube to find out what the racket was when I was testing a microcontroller routine that cycled all 128 relays one by one.

According to the audio panel, vroom is setting the sample rate to 16kHz. This matches the Indigo2. It locks me out while running the game and I can't change it, although I can when vroom isn't running.

I just picked one up with identical specs, and I'm pretty sure from the same seller. I frequently used (but did not administer) HP-UX 9 and 10 back in my grad school days, and have an old 735 with 10.20 in my collection, but this is my first experience with HP-UX 11i. The CDE interface really takes me back. The FireGL X1 runs my 1600SW great at its native 1600x1024 over a DVI through the MLA.

You're right about it being quiet, I don't think I've ever run across another air-cooled tower machine as silent as this one. I've got an HP xw8200 at work (very similar case), but it's a lot louder than the C8000. This is a very nice PA-RISC workstation. I'm tempted to replace my PowerBook G4 as a file/download server with this C8000 despite its power consumption. The fact that I can't run the PowerBook with the lid closed has always irritated me, but this thing would run fine headless.

Unlike yours, my case was unlocked but didn't come with the pedestal. There are several available on Ebay, how important do you think the pedestal is? There aren't any cooling slots underneath the machine, but I find it hard to believe the pedestal is purely cosmetic.

FYI even though my case unlocked I brought home the keys to my xw8200 and they did indeed work with the lock on the C8000. My keys are labeled "301". Could be good to know if you want to pick up some keys for it.

Thought I would let you know that I followed your advice and sent the seller a message. I had already left him positive feedback, so when I didn't hear back from him I wasn't too surprised. However, today an enormous box arrived via FedEx with the missing base in it. (The box could have held two complete C8000 workstations plus bases. ) I was quite surprised and pleased! I'm definitely adding him to my favorite sellers list.