[Coco] VCC Emu problems

[Darren A.]

> >One big problem with using a 1.2MB  5.25 inch floppy drive is that the 
>head
> >steps at a finer resolution (96 tracks-per-inch I believe). A 5.25 inch 
>CoCo
> >floppy has 48 tracks-per-inch, so VCC would need to step the head twice 
>for
> >each track. This might work for READING CoCo floppies, but if you WRITE 
>to
> >the disk, it only writes on 1/2 the width of the track. This could make 
>the
> >disk unreadable on a CoCo 5.25 inch drive.
> >
>And don't forget that the 1.2 meg drive spins at 360 rpm, not 300, and that 
>it
>expects its data to 500 kilobaud, not 250 kilobaud.  If you can find the
>jumper that slow it down to 300 rpm, then its a 100% functional replacement
>for a 720k drive.  The comments re the track width are spot on though.

I believe VCC is using the fdrawcmd.sys driver for accessing real floppy 
disks. This is the same driver I use in my CoCoDisk utility.  Programs using 
this driver can configure it to use a data rate of 300 kbps, thus allowing 
you to use a drive spinning at 360 rpms. Whether or not VCC provides this 
level of configuration is unknown to me.

Darren

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