Re: IIe 3.5 disk drive controller card

[Roger Johnstone <rojaws@orcon.net.nz>]

In <qh7jkyrat1.fsf@ruckus.brouhaha.com> Eric Smith  wrote:
> Ed Eastman <noone@nowhere.net> writes:
>> The Apple 3.5" drives all have in common that they have a variable
>> rotation rate and can read the 800k 'standard' formatted DD disk 
>> media.
> 
> All except Apple's earliest 3.5" drive used on the Lisa 2 and original
> Macintosh, which only did 400K single-sided DD format, and recent
> internal 3.5" drives on Macintoshes, which no longer support GCR.

A minor correction: all Apple Macintosh drives can read and write GCR 
disks. Macs originally used variable rotation rate drives, but around 
the intoduction of the first Power Macs Apple switched to using cheaper 
drives with a fixed rotation rate but which varied the data rate instead. 
These drives and/or disk controllers are the ones that have problems 
making ProDOS 800KB disks, at least using Disk Copy.

-- 
Roger Johnstone, Invercargill, New Zealand
http://vintageware.orcon.net.nz/
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