[Coco] Read Coco floppies in my PC

[Darren A]

On Tue, Mar 20, 2012 at 3:22 PM, Chad H wrote:
>
> I've always had a peculiar behavior between my CoCo Drives and my MS-DOS
> system with DSKINI/RETRIEVE....
> When I DSKINI a disk on the CoCo system, the RETRIEVE on the MS-DOS PC would
> have errors reading it. No other problems have been encountered anywhere!
> The same disks read/write fine in all my CoCo Drives.


This is a known problem with some PC floppy controllers.

When you format (DSKINI) a floppy on the CoCo, it puts a fairly small
gap between the index hole and the first sector on each track.  The
Western Digital chip used in CoCo controllers has no problem with this
small gap, but some PC controllers will turn off their address mark
detectors for a short period following an index pulse.  This causes
the PC controller to often miss the address mark for sector 1,
resulting in I/O errors.

The solution is to always format the disks on the PC since it will
place a gap at the beginning of each track that is large enough for
both the PC and the CoCo.

Darren