Re: Disk ][ vs Unidisk vs Duodisk vs //c external disk

[spec@vax2.concordia.ca (Mitchell Spector)]

In article nathan@visi.com (Nathan Mates) writes...

>In article <58qo57$r54@nntp.ucs.ubc.ca>,
>Tim Shoppa <shoppa@alph02.triumf.ca> wrote:
>>Starting 1979 or so the only Apple II disk drives I had ever used
>>were Disk ]['s on ]['s, ][+'s, and //e's.  I've recently begun
>>running across quite a few drives with 19-pin D connectors:
>>Unidisks, Duodisks, and //c external disks.  I've also begun
>>entertaining the thought of buying a IIgs.  A few questions:
> 
>>1.  Am I correct in assuming that I can just daisy-chain these
>>drives onto each other?
> 
>   Disk ][s don't really have a port in back to daisy chain off,
>so I'd expect that they'd be last on a chain.

    Disk II drives do not have a daisy-chain port, period. :) 
They definitely have to come last in a chain, assuming you've 
built an IDC20->DB19 adapter.

    As well, there is no daisy-chain port on the DuoDisk 5.25
or Disk //c external, both of which would also have to follow
last in a chain. The UniDisk 5.25 and Apple 5.25 are the only
Apple II 5.25" floppy drives Apple made with daisy-chain ports.
(Apple III external 5.25 drives are another story).

Mitchell Spector
spec@vax2.concordia.ca