[Coco] again 3.5" drive

[Frank Swygert]

I thought the lines you have listed as "motor on" were "side select", especially on the CoCo cable. I know you can have only three double sided drives on the CoCo or four single sided drives, as the "side select" line is used to access drive 3 (#4 physical drive). Or did you not list the side select and drive select 3 lines? 

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Date: Thu, 24 Apr 2008 10:44:20 -0700 (PDT)
From: Jim Hickle <jlhickle at yahoo.com>

The CoCo floppy controller and floppy drives
 use pins 10 thru 16 for these signals (odd numbered
lines are grounded):
10 - Drive Select 0
12 - Drive Select 1
14 - Drive Select 2
16 - Motor On

Each drive is jumpered as 0,1 or 2.
Line 16 turns on motors of all drives.


PC controllers are different:
10 - Drive 0 Motor On
12 - Drive Select 1
14 - Drive Select 0
16 - Drive 1 Motor On

ALL drives (all two of 'em) are jumpered as Drive 1.
Cable lines 10 thru 16 are twisted for Drive 0
(remember it is jumpered as Drive 1).  Since these
lines have been reversed, the drive still gets 
Drive Select on line 12 and Motor On on line 16.

-- 
Frank Swygert
Publisher, "American Motors Cars" 
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