[Coco] Re: 3.5" Floppy format

[John E. Malmberg]

Theodore (Alex) Evans wrote:
> Personally I feel that the "96 tpi" bit (bit 1 of byte $10 of LSN0)

I am missing quite a bit of the context for your post, and an assuming 
that this is something specific to the OS-9 operating system.

As you point out, since all 3.5 inch drives are 135 tpi, no double 
stepping is ever desired, even if you are using only 35 or 40 tracks.

It is only 5.25 720K or 1.2M drives that should be concerned with double 
stepping when reading 360K floppies.

Is this information stored on the actual floppy?  That would make many 
backup type operations a problem, as many of them do make complete 
images, and that includes copying images from 360K floppies on to the 
first 360k of a 3.5 inch drive with out changing any data.

The device driver is the only place that I can see needing to know this 
information.

-John
wb8tyw at qsl.net
Personal Opinion Only