3.5" drives and tape drive in Unix PC

[Brad Isley]

In article <22605 at pasteur.Berkeley.EDU> sjohn at cory.Berkeley.EDU (John Sasinowski) writes:
>	I am interested in adding a 3.5" drive to my Unix PC to make
>backing up the hard disk easier.  Jameco Electronics has a drive that
>is listed as a 720K drive for an IBM PC.  Will this work in my machine?
>If so, will it give me 800K on a disk?  The drive is manufactured by
>Sony.

I waited a while for the correct response, but it didn't come.  Anyway, here's
the sketchy requirements for making a 3.5" floppy work in the 3b1.  If it's
configured for an IBM PeeCee it  WILL NOT WORK.  Sony's recent offerings in
the 3.5" size are hardwired for PeeCee compatibility - no jumpers. :-(
I know it won't work, I tried.  Gotta have jumpers.  I have a Mitsubishi in
mine.  Works great.  Stores 1560 blocks on a disk with a default file system.
(what's that, 780k?)  I have made an older Mitsubishi work, plus a Teac.
I had to experiment with both brands to get the jumper configurations right.

For the Mitsubishi, short the following jumpers:
SR MM IS DS0
Finding SR on older drives may be difficult.  It uses pins common with DC
and (DC).  Examine the silk screen closely on both sides of the header.
Also notice that you must twist the data cable when installing
Mitsubishi drives.  It's very tight after the twist.

For the Teac, short the following jumpers:
RY DS0

All jumpers not mentioned above must be open.

Hope someone can use this info!
-- 
Brad Isley, yer local tools blacksmith.
---------------------------------------
What, me worry ?