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Simplest way to get a bootable floppy to format a disk on a Powerbook on MacOS

Den2016

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Joined
Aug 18, 2016
Messages
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Location
Toronto, Canada
I'm new to MacOS software, I'm learning but I'm encountering issues that I find strange that I don't have an explanation for.

From my experience with Basilisk II and reading online, it seems that for a disk to be bootable all it needs is:

1. HFS format
2. System Folder
3. System file
4. Finder file

I have a PB140 with an external SCSI zip disk and a floppy drive (no internal SCSI disk). I'm trying to boot from a floppy so
that I can initialize a SCSI zip disk so that I can create a A/UX partition (or Linux ext2 partition if possible). I'm trying to run
Linux.

Online reading suggests that Disk Tools for any of System 7.0.1, System 7.1 or System 7.5.3 would work. But unfortunately
for every image that I try, it fails. It fails because the PB140 won't accept the Disk Tools floppy and just spits it out.

I'm reading online that some PB require System Enablers but according to some sites this
is not required for PB140. So what am I doing wrong? The floppy drive works fine because I can boot a Linux boot floppy (it
reaches to the point where it mounts a root disk).

Thanks
P.s. I need a A/UX partition in order to install ext2 file system on it?
 
What kind of hardware and software are you using to write the disk image?

According to the specs, the PowerBook 140 has a 1.4mb floppy drive. The good news is, this means you should be able to write any Macintosh 1.44mb floppy disks using at least any Windows machine with WinImage, even with a lobotomized USB floppy drive.

Since you mention Linux, I hope you are not trying to write disk images with "dd" or a similar raw-writing tool. The problem is most Macintosh disks images floating around are actually in Apple DiskCopy format, not proper "raw" format.

That means they have some garbage at the beginning of the file that is meaningless in the PC/Windows/Linux world. The file will be larger than a normal 1,474,560 byte image. Writing with dd/rawwrite will cause the contents of the disk to be skewed and unrecognizable. WinImage, however, will usually recognize such files and write the disk correctly.

Also, if the files are smaller than 1,474,560 (and not 400/800k images) then the disk may be compressed with DiskCopy's proprietary compression and can only be expanded on a Mac or an emulator)
 
I downloaded BinHex formatted floppy images from http://www.macfixer.com/vintage-software/ .
For example the System 7.1 files I downloaded the split files, i.e. BinHex individual floppy images.
I decompressed with the standard Archiver utility on a Macbook Pro (2015). And then I dd the
image file to a floppy (USB floppy). So for instance, the Disk Tools.img file mounts successfully and boots
successfully on Basilisk II (on my Macbook Pro). The disk image is a full 1,474,560 bytes.

When I mentioned a Linux floppy, I'm referring to some floppy images that are provided in the EMILE
project (https://sourceforge.net/projects/emile/files/). They are old files but they are properly formatted
which means that my PB140 boots correctly (from the floppy into a boot loader (looks like GRUB) which
then boots a kernel.

What I'm trying to do is initialize a zip disk so that I can create a A/UX partition so that I can get a Linux
root file system on it (I believe that's what I need). When the EMILE floppy boots, it will load the kernel
and then attempt to mount a root file system, however, it doesn't know how to mount the zip disk
and I believe it's because the zip disk has got a DOS partition scheme.

I just realize that I can try and use another PB that I have (to partition the zip disk). I'll give that a
try (so I don't have to worry about initializing a zip disk from booting off a floppy.
 
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