1.44M floppy on Color Computer (was Re: Ebay reaches new low)

From: Dwight Elvey <elvey_at_hal.com>
Date: Wed Nov 10 20:06:08 1999

ard_at_p850ug1.demon.co.uk (Tony Duell) wrote:
> > Another factor, the sectors for DOS formatted disk are
> > 512 bytes long. Any loop that only does 256 won't make it.
> > It would need to be formatted with more wasteful 256 byte
> > sectors. This has been a good line of thought ;)
>
> Is this a problem? Firstly, who says you'd use an MS-DOS format -- the
> CoCo uses 256 byte sectors for virtually everything, and I'd suggest
> keeping to that on the HD disks, just having more of them. As to being
> more wasteful, well, MS-DOS 360K (and 720K) disks fit 9 512byte sectors
> on a track, the CoCo fits 18 256byte sectors. Looks the same to me.
>
> And the 6809 index registers (X, Y, etc) are 16 bit registers. The loop I
> posted (and the ones others have posted) will transfer 512 bytes if you
> want them to. Whether there's a speed penalty when you cross a 256 byte
> boundary I don't know -- I don't remember anything like that in the 6809
> instruction set, but it's been many years.

Hi Tony
 If this is true, it looks like it is possible to work
wonders with this chip ;) The reason for doing DOS compatable
disk is that it makes transfers of info a little easier.
Dwight
Received on Wed Nov 10 1999 - 20:06:08 GMT

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