Re: ][+ auto-boot from hard d

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

Jeff Brielmaier <jeff.brielmaier@psl-online.com> wrote:

> SA>One question, though. Can the Apple ][+ automatically boot from the hard
> SA>drive? When I power the computer on, it instantly starts accessing the
> SA>floppy drive in slot 6. If I just let the floppy drive spin empty, and go
> SA>ahead and do a CTRL-RESET, I get a cursor and can type PR#7 and then the
> SA>computer will boot up from the hard drive just fine.
> 
> No, Unless you have the capability modify/re-burn a ROM chip.
> 
> The problem is that the Apple SCSI card isn't identified as a bootable
> interface card.  [snippage]

>      Original ROM --> 0000: A2 20 A2 00 A2 03 A2 00
>      Change it to --> 0000: A2 20 A2 00 A2 03 A2 3C
> 
>      i.e. Change the byte at offset 0007 from '00' to '3C'.
> 
> After you have mande the byte change and programmed the replacement EPROM, you
> will be able (should) to boot from the SCSI drive.

One warning about this idea: the patched ROM will mean that the SCSI
card is not recognised as a SmartPort device.  This will prevent most
utilities from recognising it as a SCSI card.  In particular, it is
likely to prevent all partitioning software from working with the card.

(If you managed to run ProDOS-8 2.0 or later on the II+, it would also
prevent ProDOS's drive remapping from working, so you would be limited
to four partitions if the card was in slot 5, two if it was in another
slot.)

-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand