[Coco] 3.5" drives

[Willard Goosey]

>Date: Fri, 20 Aug 2004 11:14:41 -0400 (EDT)
>From: James Dessart <james at skwirl.ca>

>I'm interested in putting a 3.5" drive on my CoCo, since 3.5" floppies are
>still available in stores, and I do have a couple of Macs that can
>read/write to them (even in PC format).

They're sweet.  Short of a hard drive, nothing beats having 720K of
room for stuff on one disk.
>
>What I'd like to have is the double sided 5.25" and add a 3.5" to the
>system, getting rid of the single-sided drive. Will this work with RS-DOS?

RS-DOS, unfortunately, will think your 3.5" is a 160K drive, just like
all the others... This can be patched, but that gets funky...

>And what would I have to do to get it working in OS-9?

If you had it, say, as drive 1, dmode the descriptor and build a new
boot disk.  

> Could I use high density diskettes?

Your SCII isn't capable of reading/writing high density.  The only
CoCo disk controller that could is the original FD-500.  And getting
that to work aparently takes parts, time, and a good oscilloscope.

There have been many dire warnings about using high-density disks
formatted double density.  I have had problems that may have been
caused by this.  I dunno.  YMMV.

>Would I be able to read MSDOS FAT formatted diskettes from OS-9?
>Would I need to make any hardware changes?

Under OS-9 you need rbf version >11 (I think) (NitrOS-9 rbf works for
this) and the PCDOS program on rtsi.  It doesn't know about Y2K and it
doesn't know about vfat long file names, but other than that it works
great.  If you have other dinosaurs around, PCDOS also reads PC 360K
disks, and Atari ST disks.

>I have an order for DriveWire placed, so that'll maybe alleviate my desire
>to do this... :)

Local storage is always a good thing. :-)

Willard
-- 
Willard Goosey  goosey at sdc.org
Socorro, New Mexico, USA
"I've never been to Contempt!  Isn't that somewhere in New Mexico?"
   --- Yacko