Re: Creating a CD for a use on an Apple IIgs?

[pitz <pitz.wong@gmail.com>]

On Monday, November 12, 2012 5:28:16 PM UTC-8, pitz wrote:
> On Monday, November 12, 2012 2:44:46 PM UTC-8, waynej...@gmail.com wrote:
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> > I haven’t tried the developers CDs on a IIe but I have burned ProDOS CDs with a Mac. They’re useable on any Apple II with a CD drive and running ProDOS. I’ve had a CD drive connected to a IIgs, IIe, II+ and a II. I’ve booted off a CD with the IIgs, IIe & II+.
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> > Last time I made a ProDOS CD I used a Mac 7600 running OS 9. Don’t recall which version of Toast. 
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> > The way I did ProDOS CDs was by blind SCSI copy. I'd set up a Hard drive with the data and partitions I want. Then I'd hook it up to the computer with the CD burner. Leaving the hard drive off I'd boot the Mac. After the Mac had booted I'd turn on the hard drive. The reason I did this was so the hard drive wouldn't mount and so the MacOS wouldn't change or add anything to the HD. Then with Toast I'd use Device Copy to choose the unmounted hard drive and burn it to a CD. That'd give me an exact copy of the HD and if it was bootable, then the CD was bootable. Also this way the Mac doesn't need to be able to understand or deal with ProDOS.
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> > I don’t know if there’s a way to do this on a PC
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> > On Monday, November 12, 2012 10:16:59 AM UTC-8, pitz wrote:
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> > > There's probably even a way of creating CDs with ProDOS partitions.  The first few Apple Developer CDs (the Phil and Dave CD?) had a ProDOS partition, aside from the HFS partition.  Could these CDs be readable from an Apple II/e (equipped with a SCSI or IDE card)? 
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> > > /pitz
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> The method you mentioned essentially treats the CD like a hard disk, and can also be used for booting the system, like any ProDOS bootable device.
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> An interesting idea for the Apple IIgs is to have a bootable ProDOS CD, but subsequently take advantage of the ISO9660 or HFS capabilities within GS/OS.
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> From some of my notes (back when I was looking into this), this might be possible by creating a multi-session CD.  However, a lot of older drives do not recognize multi-session CDs.  It was primarily used for writing data incrementally to the CD in multiple "write" sessions and chaining the sessions together.  And I don't even know how the IIgs FSTs treat the multiple sessions.
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> Another idea that will not work is using an "El Torito" boot mechanism.  This was mainly for the PC (though I think nothing in the specs limits its use to the PC).  The Apple II/IIgs likely does not know how to bootstrap using the El Torito mechanism.
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> A more probable approach is to use an ISO9660 CD with "overlaid" bootstrap systems.  NEXTSTEP/OPENSTEP used this to bootstrap its installation CD in multiple platforms (the NEXT systems and SPARC systems, and partially on PCs).  There is a 32KB space available at the start of an ISO9660 image.  Hybrid HFS/ISO9660 CDs make use of this by putting an Apple partition map into this space.
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> Does the SCSI card respect an Apple partition map during the boot process, to boot from a specific partition?  I suspect some cards do, and some don't.
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> If an Apple partition map is ignored, 32KB is enough to create a ProDOS file system, but possibly containing only ProDOS.  Even just adding BASIC.SYSTEM would overflow this space.  Not enough to bootstrap GS/OS and load its FSTs.  But there is some space available after the ISO9660 volume descriptors.  Could we hide the ISO9660 volume descriptors as a single ProDOS file, and extend the ProDOS file system beyond them?  Worth a try...
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> /pitz

Don't know how I missed it, but that awesome utility CiderPress can recognize and work with mixed-partition (combination of ProDOS and HFS partitions) disk images.  I don't have access to an installation right now, so I'm only reading from the CiderPress features list.  I couldn't tell if it supports "creating" mixed-partition disk images.  Nonetheless, you can start with an image of one of those early Apple Dev CDs (they do have a bootable ProDOS as the first partition) and add/replace files within CiderPress.

Note that these mixed-partition CDs are purely ProDOS and HFS.  They don't have an ISO9660 file system and are different from so-called superpositioned "hybrid" CDs where the HFS and ISO9660 file systems are overlaid upon each other.  For the IIgs, this means you don't need to have HS.FST (you would only need HFS.FST).

/pitz