[Coco] floppy controller update

[Phill Harvey-Smith]

Chuck Youse wrote:

> On Sun, 2008-07-06 at 16:13 -0400, Chuck Youse wrote:

> The more I think about this, the more I think it must be an interleaving

> issue.  Consider that the sectors are most likely laid out in order by

> Linux's fdformat.  Consider that I appear to be getting something in the

> neighborhood of one sector every 200-250ms, and then consider that at

> 300RPMs, one revolution takes about 200ms.  Bingo.

> 

> Does that seem right?  Is anyone even listening to my jabbering

> anymore? ;)


Yeah that seems reasonable, IIRC stock RS/Dragondos uses a 1:4 
interleave, and most other DOSes of that vintage also seemed to use 
interleaving other than 1:1, which is as you say prolly what Linux is 
laying down when formatting, which is pretty much the reason that I 
always format CoCo/Dragon disks in the actual machine and then write 
them in Linux, because interleave is set when formatting, linux will 
write it correctly, however it always formats with 1:1, dunno if there 
is a way of over-riding this tho.

Cheers.

Phill.

-- 
Phill Harvey-Smith, Programmer, Hardware hacker, and general eccentric !

"You can twist perceptions, but reality won't budge" -- Rush.