[Coco] Dmode Settings

Stephen H. Fischer SFischer1 at Mindspring.com
Sun Jun 3 23:47:42 EDT 2012

----- Original Message ----- 
From: "Dean Leiber" <adit at nationsdial.com>
To: "CoCoList for Color Computer Enthusiasts" <coco at maltedmedia.com>
Sent: Sunday, June 03, 2012 8:06 PM
Subject: [Coco] Dmode Settings


Before someone tries to say something different, for a 720K 80 Track 2 Sided 
disk the correct DNS setting is DNS = 3.

Yes, there are lots of floppies of the 3.5" size with DNS = 1 which is 

I had a 3.5" 720K 80T 2S drive and a 5.25" drive which was also 80T 2S and I 
was able to switch /D0 and /D1 with a switch.

OS-9 has a feature that if the 80T 2S 5.25" drive has a lessor format disk 
in it, it will read it.

Thus, one 5.25" drive could read 80T floppies, 40T floppies, 35T floppies 
and single and double sided ones with no change to the descriptor.

Trying to write to the lessor formats, you better have used a bulk tape 

I fear that the number of 3.5" floppies out in the world with DNS = 1 is 
vastly greater, I my self have none.


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