Many of us may remember old threads about getting USB on a NuBus Mac. Well, ther is a project at http://microusb.org/ that is working on putting USB on old machines. They use a fairly "open" and compatilbe chip for Ataris to do USB. There is also an Apple II USB project that is in the works.
So, with all that, and the nice AtariMax USB cart I'm a tad suprised some enterprising NuBus hacker hasn't come up with something for the much more powerful Mac II and beyond... 
The interface they've built here uses the same controller chip I suggested in this thread. I rule. ;^)
Getting the hardware stuffed into an NuBus slot would be the easy part. Writing the drivers would be be the nontrivial bit. Particularly if your goal was to make this bastard USB port work with the OS'es (8.1 and higher) build-in USB driver framework. (My guess is that would approach "impossible" without the OS source code.) Writing one-off drivers to work with keyboards/mice/simple storage devices might be easier.
--Peace
I was thinking that someone with much better knowledge than me might be able to write a ROM for the card so that one might be able to use USB HID devices as ADB from a NuBus card. Getting full OS-level support is quite a far reach. Of course once you get a card built and some sort of low level interface ROM then building support for a *BSD or LINUX wouldn't be too hard.
I would think the best hope of getting USB on a NuBus PPC Mac would be to put it on a G3 accelerator card. It would bypass the rather thorny Nubus problem and also have external access (on 7100s and 8100s at least).
Mac OS 8.6 - 9.22 support USB reliably, but not via NuBus so that may really be a dead end unless someone writes a NuBus USB driver. On the PDS it may be made to appear as an on-board USB port which the Mac OS already supports.
With USB controllers being so cheap nowadays, perhaps Sonnet can include USB with its next batch of G3 accelerators....if they intend to still develop those accelerators.
Personally, I prefer NuBus PPCs over non-G3/G4 PCI Macs. Nice compact form factors, easier to find RAM, etc.
I've sold all my PCI power Macs (75/76/96) but moved back to NuBus PPCs and Beige G3s for running Mac OS 8/9. NuBus PPCs rule!
The problem with limiting such an animal to only NuBus PPC machines is that it locks out all of the people with non-PPC NuBus machines. A NuBus USB card & driver that works on both 68k and PPC machines opens up marketing possibilities to a much wider audience and makes it much more feasible financially for someone to make a go of it.
I've had good experiences with PPC Macs, but I also remember supporting the 601 machines before the G3 upgrades were available; it wasn't pretty. The 68k machines were MUCH more stable than the average 7100 or 8100. Adding a G3 upgrade card to one of those troublemakers makes a world of difference. But I still love my 68k NuBus machines.
yeah i agree, Macintosh IIci & quadra 950 4 ever
Shucks, you guys are making me feel remorseful. I just parted out a IIfx I recently found and put it all up on eBay. The fourth one I've owned. It's hard not to love those old machines and want to hold onto them for any reason at all. Too bad I don't have the space. At least, I sold the ROM in a blink of an eye for $50, and the Thunder IV video card not too long after that. Last time I checked, the motherboard and RAM and floppy drive were still available, so if anyone's interested:
my auctions
If I knew there was a USB adapter around, I probably would have held onto it. That would certainly resurrect it uses. Keep on keeping on, tech wizards!
I read up a while back on Nubus, with the vague idea of seeing if a Nubus IDE card was possible. From what I saw, the hard part is Nubus - it's an intelligent protocol, and of course, all the intelligent bits are proprietary and documentation is impossible to get.
Unless you were a Nubus card developer back in the day, and a packrat ....
A PDS card would probably be "easier", yes.
It's somewhat ironic I suppose, but... there'd probably be a lot more interest in creating hardware add-ons like this for ancient Macintoshes if MacOS were a truely "dead" platform, like Amiga or Atari ST (for example). The dead platforms attract the truely hard-core dedicated hacker types who will go to insane ends to add functionality to the machines they just can't part with. As it is, well, let's be honest. What's the point of making a Nubus USB card when you can get a perfectly good PCI Macintosh for less then what such a card would cost? Since the more modern machine *exists* and is readily available there's simply much less motivation to bother.
Anyway.
--Peace