December 12, 1993     


     My 1.2M FD that I had used with my 286BB, and now 
my 386BB, decided that it really did not want to work 
anymore, (Actually, it sort of still does, but give me
a lot of errors/corrupted file messages that aren't 
real, as confirmed by other PC's).  I seized upon the 
opportunity to buy a new Teac Dual Drive, one that has 
both a 5.25" and 3.5" in one 1/2 height case.

     When I bought the thing, I noticed that there was 
only one (1) connector on back.  The cable coming off 
the BB, has two (2) connectors, 1 before the twist, and 
1 after.  Well, I connected the last connector (after 
the twist) to the new drive.  No matter what I did in 
BBsetup or PC Prefs, I could only access the 5.25"!  
When I connected the first connector, (before the twist) 
I could only access the 3.5"!  In both cases, when the BB 
booted up, it would tell me about a drive failure, as if 
I didn't already know...;-).  So now, I could access either 
floppy drive, but only one at a time with a cable change.
I concluded that the drives were working, but the BB or 
cable did not "speak" correctly.  It turned out that it 
was the cable.  Talking to Kelly, one of Harv Laser's 
friends, whom I had ordered a couple of external 3.5" 
SCSI cases earlier in the day, found out which pins on 
the BB cable were what.

     The twist of the BB cable consists of pins 10-16.  
They are labelled as follows before the twist;

Pin 10 - Drive Select 0 (DS0)

Pin 11 - GND

Pin 12 - DS1

Pin 13 - GND

Pin 14 - DS2

Pin 15 - GND

Pin 16 - Motor On

     Kelly concluded that since software drives whether 
accessing drive A or B, that the drive motor was not enabled.
I jumpered pin 16 and 12, before the twist, and voila, both 
drives work!  If you connect the connector on the BB cable 
after the twist, the 5.25" will be drive A and the 3.5" will
be drive B.  I did not like that, so I connected the connector 
before the twist, and now I have the 3.5" as drive A, and the 
5.25" as drive B.  Making the jumper permanent was no problem 
as the drive comes with a 34 pin to edge connecter converter,
and I just soldered the jumper there.  Of course, I have told 
BBsetup which drive is which size.  PC Prefs also knows that
both drives are internal.

     I had not seen any information on the nets that addressed
the "Dual Floppy Drives", both Teac and now I think NEC makes 
them too, so that's the reason I posted these tidbits.


Phil


Since posting this article on UseNet (comp.sys.amiga.emulations)
several people have e-mailed me, about having no problems with
their Teac or Cannon dual-drive out-of-the-box with their 
bridgeboard.  Maybe I got a lemon..., but the drive has been 
working great for over 2 months.