Re: Looking for a Micro SCI disk controller

[mjmahon@aol.com (Michael J. Mahon)]

Bill Garber wrote:

>Combining the 2 answers tells me that the hardware governs
>whether a drive is working at 13 or 16 sector, and adding
>everything else I have heard. Thanks everyone for clearing
>that up.

Not exactly...

As has been pointed out, the only reason that the 16-sector
(later) controller cannot boot 13-sector disks is that the boot
ROM changed.  The 16-sector controller is perfectly capable
of reading and writing 13-sector disks with DOS 3.2 software.

This is why a pre-boot with the BASICS disk will allow you
to boot a 13-sector disk on a 16-sector controller--it provides
the missing 13-sector boot code.

Once the software is booted, the 16-sector controller works
perfectly with either variety of disk.

(Of course, the 13-sector controller (state machine ROM) will
_not_ work with 16-sector disks.)

-michael

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