[Coco] Read Coco floppies in my PC

[Aaron Wolfe]

Your results are atypical.

The problems between 1.2mb drives and 360k drives are very well known.
 This used to be common knowledge, but I guess its been a good long
time since anything regarding floppy disks was well known.

For instance, this microsoft article details the problem:

http://support.microsoft.com/kb/79538

You will find further documentation in the wikipedia article on floppy disks:

http://en.wikipedia.org/wiki/Floppy_disk#5+1.E2.81.844-inch_floppy_disk

The crux of the issue is that 1.2MB FDD use a narrower track than 360k
disks by design.  The read head on a 1.2MB FDD can easily read the
wide tracks written by a 360k drive, and it can also read the narrower
tracks written by 1.2MB drives.  However, 360k drives cannot usually
read the narrow tracks written by a 1.2MB drive.  This means writing
to a 360k disk with a 1.2MB drive generally renders the disk
unreadable by 360k drives.  This is a physical property of the write
head and not something changeable via software.


..

On Fri, Mar 30, 2012 at 11:53 PM, Chad H <chadbh74 at hotmail.com> wrote:

> I have 9 360k pc-xt drives, all fully tested to read/write disks formatted by 1.2 mb drives without problems....?????

>

> Michael Graham <mkgraham at gmx.com> wrote:

>

>>Just FYI, most double-density (360k) drives won't read double-density

>>disks written on high-density (1.2M) drives.  I tried this when I first

>>got my PCjr, and it didn't work, so I had to swap the 360k drive back

>>and forth between my PCjr and my old desktop machine until I could

>>source another 360k drive.  I couldn't get disks written in a 1.2M drive

>>to read on my CoCo, either.  However, disks written with a 360k drive

>>will read back just fine on a 1.2M drive, as long as you don't try to

>>write to them.

>>

>>On 3/30/2012 8:20 PM, Bill wrote:

>>> The drives I just got are 1.2Mb, and I have tried several times to format a

>>> 360K disk, but for some reason it won't let me. I type in the command format

>>> b: /f:360 (which SHOULD work), but it gives me an error message.

>>>

>>> Has ANYONE been successful formatting a 360K disk in XP with a  1.2Mb drive?

>>>

>>> Thanks

>>>

>>>

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>>

>>

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>>

>

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