IIfx - weird Nubus card issues on A/UX

[halkyardo]

I'm trying to get A/UX 3 stood up on my IIfx, and I'm running into a really strange problem - if the only Nubus card in the machine is my graphics card, it'll boot fine and run happily. If I add any more cards, it hangs at a grey screen with square corners, immediately after loading the kernel (I assume this is the point where A/UX Startup hands off control to the kernel). If I remove the cards again, it boots just fine. Swapping cards around between slots doesn't seem to change things either.

I first noticed this happen with a National Instrument GPIB card, I assumed that it was just a quirk with that particular card and removed it. But over the weekend I tried to add an ethernet card (an Asante MacCon 3 NB) and ran into the same problem. According to some old Usenet posts I dug up, and a few mentions on this forum, that card should be supported under A/UX.

Both the GPIB card and the Ethernet card seem to work just fine on System 7.1.

I guess it *could* be the machine itself, but I did have a working A/UX 3.1 installation running on it about 10-15 years ago (with almost a full complement of NuBus cards!). It's spent most of the intervening years in storage, but when I recapped it recently, I didn't notice any visible damage to any traces. Power supply voltages are all correct and appear to be stable.

I'm using a BlueSCSI as my disk drive, and the A/UX image from https://mega.nz/folder/8hA3AQCJ#pWUq92L70yDXlogy9lk5Dg (which I found linked in the BlueSCSI Github wiki). I also tried a clean install from an A/UX 3 ISO that I've had kicking around on my computer for years, with the same result.

Unfortunately I don't have any additional cards to test it with, but has this happened to anybody else? Any ideas where I should look?

 

[halkyardo]

Huh... the trick (at least for the ethernet card) seemed to be that I had to install Ethertalk drivers in the startup partition's System Folder, once I did that, A/UX booted fine and recognised the card. Maybe it didn't like seeing the card in an uninitialised state?

 

[Cory5412]

Thank you for sharing the update on this!

I don't know the underlying reason why but that makes as much sense as anything else!

 

[beachycove]

This may also help: A/UX will rebuild the kernel when each new (supported) Nubus card is installed, so that there is a delay on booting when you pop one in. “Patience,” as a four year old girl with a rather pious Catholic mother once told me, “is a birtue.”

 

[halkyardo]

Hmmm, it turns out the 'fix' I mentioned was just a coincidence, it had been working happily for days, and then yesterday after a reboot, it went back to its old tricks. Curious.

The hang occurs extremely early in the boot process - right at the first screen 'flicker' that you get after A/UX Startup finishes loading the kernel - normally the screen blanks for a moment, then you get a gray screen, then the cursor and rounded screen corners show up, and then the progress bar appears. The hang happens at that gray-screen stage, with no cursor, before the cursor and progress bar show up.. There's no disk activity and I've waited several hours with it stuck there. I'm pretty sure that the kernel rebuild happens later in the startup.

Booting in verbose mode with launch -v hasn't given any clues because it hangs before the console comes up.

If I pull the ethernet card it boots just fine again, I tried updating to 3.1 in case that helped, but no dice - it still hangs if I put the ethernet card back in.

 

[MrFahrenheit]

Curious: when it appears to “hang” with the network card installed, can you ping the machine ?

 

[halkyardo]

curiouser and curiouser: I hooked a serial terminal up to the modem port, and got a panic message when the hang occurs - always a bus error at the same address and PC.

I also booted it headless with the graphics card removed, and just the network card present, and it came up with a console on the serial port. I wonder if my graphics card is causing some kind of bus disturbance that interferes with other cards but doesn't affect operation if it's the only card on the bus? It's a Memory Plus 24NB, there doesn't seem to be much info out there on them. I'd noticed a bit of capacitor leakage on there and did my best to clean it up, but it seemed to be in the area of the RAMDACs, rather than the bus interface logic.

Of course, right in the middle of troubleshooting, it started working fine again without me touching anything, so that makes it a bit tricky to dig in further!

(as an aside, those little HP protocol analysers are fantastic for stuff like this, they have an auto-setup mode where they'll listen for serial data and automatically configure themselves for the right baud rate etc. which makes life a lot easier)

 

[MrFahrenheit]

curiouser and curiouser: I hooked a serial terminal up to the modem port, and got a panic message when the hang occurs - always a bus error at the same address and PC.

I also booted it headless with the graphics card removed, and just the network card present, and it came up with a console on the serial port. I wonder if my graphics card is causing some kind of bus disturbance that interferes with other cards but doesn't affect operation if it's the only card on the bus? It's a Memory Plus 24NB, there doesn't seem to be much info out there on them. I'd noticed a bit of capacitor leakage on there and did my best to clean it up, but it seemed to be in the area of the RAMDACs, rather than the bus interface logic.

Of course, right in the middle of troubleshooting, it started working fine again without me touching anything, so that makes it a bit tricky to dig in further!

(as an aside, those little HP protocol analysers are fantastic for stuff like this, they have an auto-setup mode where they'll listen for serial data and automatically configure themselves for the right baud rate etc. which makes life a lot easier)

I would think if it’s working then not then working then not, it’s not a software problem or a hardware conflict. I would lean towards failing hardware in need of recap, etc.

 

[halkyardo]

I would think if it’s working then not then working then not, it’s not a software problem or a hardware conflict. I would lean towards failing hardware in need of recap, etc.

Yeah, I think you're right. It started hanging again. I pulled the card out and it looks like they'd leaked more since I cleaned it up. Gave it another clean, and the issue went away again for the time being. This time I actually remembered to order replacement caps - here's hoping that they fit!