Downlevel

[altivo]

It's starting to look as if I need to downgrade the OS on the Amiga Emulator. It comes with 3.1, the last "almost official" release while the Amiga was still under Commodore control. The unfortunate thing about that is that the documentation for the library calls and functions were never officially published. Though I was an official developer at the time of C='s demise, I was not deeply enough into coding in C to make much direct use of system libraries. Consequently, I never obtained the draft documentation that would have explained points at which the new versions of library code differed from those in version 2.1.

The problem with doing a downlevel of the OS is that I'd need a readable set of 2.1 diskettes. There's a slight chance that I have those, but because the Amiga's floppy disk format requires a dual speed drive I can't read those diskettes in a PC compatible machine. And, as I've mentioned before, I have reason to believe that the floppy drive in the real physical Amiga here has failed. Catch-22 that.

More steamy weather, with air quality alerts because of no wind to clear stuff away. Large tiger swallowtail butterflies are flying even at night. We spotted one trying to crash through the dining room window to get to the light inside. And here it is August already. Where has the summer gone? Mostly eaten by work, alas.

I need to take some time off, for sure. From the look of the calendar though, It's not likely to happen until after Labor Day.

Comments

[corelog.livejournal.com]

I don't suppose there a way to either a) attach a virtual floppy directly to an Amiga, or b) connect over the network to a virtual floppy hosted on a Windows PC? (If you downloaded the floppy image to that. I've never gone looking for an Amiga virtual floppy image online, but perhaps you could find one...)

[altivo]

Oh sure, there's a virtual floppy format and thousands of disk images online for it. (The usual suffix is .ADF)

I have not, however, seen any images of original OS installation diskettes anywhere. Most archive sites expressly forbid uploading them.

I have many sets of real floppies here. (It took five or six diskettes to install all of AmigaOS at that time, and I was a registered developer and tester so they sent me a new set for every release candidate.) Some have been stored carefully, some not. I could convert them to ADF images if I have a workable diskette drive. Eventually I'll have time to check on that, but I know that the last couple of times I tried to read an Amiga floppy it failed. Whether that was old media or the drive itself I'm not sure.

[altivo]

Oh, and no, I don't think network hosting by a PC or Mac works with the floppies or images. It would work if you had all the individual files unloaded to a normal directory on the remote host machine and just needed individual file access. Amigas can do SMB/Samba file sharing or NFS/Unix file sharing. But booting and installation requires Commodore style hardware access. Amiga floppies were read and written a whole track at a time, not by individual sectors the way most current equipment does it. That approach needed more RAM for buffering and an efficient deblocking algorithm, but they had both. The saving in sector gaps and control leaders let them cram 880K onto what would normally have been a 720K DSDD floppy. Doesn't seem like much today, but in 1988 that was pretty impressive.