[Coco] Connect CoCo Floppy drive to Windows PC

Gene Heskett gene.heskett at verizon.net
Sun Jan 18 16:10:59 EST 2009


On Sunday 18 January 2009, Bill Barnes wrote:
>IIRC, the PC Floppy controller is "sleeping" because when they designed it,
> they designed the supporting structure to reset the FDC chip every time the
> sector 0 sync hole came along. The CoCo didn't do that. Because of this
> there is an unused gap between the sync and chip "reset" recovery before it
> can write or read to the disk. It's in that gap, where the CoCo writes
> because it isn't clobbered over the head every sync to reset, that the PCs
> have a difficult time reading or writing to a CoCo disk that was formatted
> on a CoCo. Formatting a CoCo disk on the PC eliminates the unreadable time
> frame, as far as the PC is concerned, and the CoCo could care less that
> that gap exists.
>
I had heard there was a gap timing problem occasionally, and it has bothered 
the coco.  But this is the first time I've read a cogent explanation of it.  
Thank you.

FWIW Bill, I find that when I am doing nitros9 disk images here in this linux 
box, Fedora 8, generic kernel local build, that I must first format the disk 
on the coco in order for it to work correctly, otherwise dd gets a tummy ache 
a few sectors into the write and dumps out.  If anyone knows the secret of 
properly formatting a coco disk on linux, I would appreciate a hand.  
Software to use, command line to use, etc, please.

-- 
Cheers, Gene
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
You cannot propel yourself forward by patting yourself on the back.



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