Re: monitor on IIgs

[Roger Johnstone <rojaws@es.co.nz>]

In <YMydnabDyIvw7_SjXTWcoQ@comcast.com> Bill Garber wrote:

> Yes, for example, I placed a superdrive controller in slot 5 of my IIe,
> then attached the 800k drive. Leaving the 5.25 empty of disk, it sat
> there waiting for one, never scanning down to slot 5 for the 800k.
> Why? Whine to me please. ;-)

Because the ROM on Apple's 5.25" disk drive controller card was never 
updated to handle it. On a IIc or IIgs the boot ROM gives up after a 
number of tries at finding a bootable disk and either passes control to 
the next disk controller or gives the 'check disk drive' error. Probably 
the ROM on the ol' 5.25" controller just wasn't big enough back in '78 (
I think it fits entirely into the 256 byte slot ROM space), besides 
which no other controllers existed for it to pass control to except 
another 5.25" controller. Apart from a minor ROM update for the move 
from 13-sector disks to the DOS 3.3 16-sector disks, and a minor card 
redesign to use the D19 drive connectors, that card used the same design 
from 1978 to 1992. Now, in computer terms, that is _old_, but if it's 
only slightly broken, don't fix it :-)

-- 
Roger Johnstone, Invercargill, New Zealand

Apple II - FutureCop:LAPD - iMac Game Wizard
http://homepages.ihug.co.nz/~rojaws/
________________________________________________________________________

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