Re: SCSI Interface for A2GS

[dempson@actrix.gen.nz (David Empson)]

william strutts <wrstrutts1@home.com> wrote:

> David Empson" <dempson@actrix.gen.nz> wrote in message
> 1evq79c.1gu1wrxivf8lcN%dempson@actrix.gen.nz">news:1evq79c.1gu1wrxivf8lcN%dempson@actrix.gen.nz...
> > william strutts <wrstrutts1@home.com> wrote:
> >
> > > Is there any problems associated with reading CD-R's?
> >
> > This will depend on the CD-ROM drive and the specific type of dye used
> > by the CD-R media (possibly influenced by the writer used and the burn
> > speed), as usual for CD-R.  :-)
> 
> What types of dye are we talking about?

I wasn't referring to any specific dye, just the general problem where
CD-R media with one type of dye doesn't work in some drives, while
another dye will work fine in the same drives.  It is usually only a
problem with audio CD players and older CD-ROM drives.

The only way to determine this is to try a test burn of a CD and see
whether the target drive will read it.  If it doesn't work, try another
brand.

In some cases, the burn speed also influences things, and this interacts
with the CD writer and media in varying ways.

To burn a CD at faster speeds, the CD writer has to increase the
intensity of the laser and use a shorter burst.  Some combinations of
media, drive and speed will produce a CD which works less reliably.  By
reducing the write speed, you may be able to get a better result with
the same CD writer and media.

> > If you are using an Apple CD-SC, CD-SC+ or CD-150, it will _not_ support
> > a multi-session CD.  Only the first session will be accessible.  (This
> > will prevent accessing the data on an "enhanced" CD with audio in the
> > first session and data in the second.)
> 
> Will they read a CD-R disk?

When I had access to any of these drives, CD-R wasn't around.  CD-R was
designed to be compatible with most older CD-ROM drives, so they
_should_ work.

CD-RW definitely won't work.

> > There is of course the issue of the file system as well.
>
> I would be formatting the disk to be read with a IIgs.  I was thinking
> of making backups of all IIgs files so that they don't get lost on aging
> magnetic media.

In that case, you will have to use HFS, or do a straight SCSI copy from
a hard drive with ProDOS partitions.  (An HFS CD will be difficult to
access under ProDOS-8.)

I'm pretty sure the High Sierra/ISO FST on the IIgs won't handle
Macintosh Extensions, which are required if you want to be able to
retain resource forks and file types, so you won't be able to use ISO.