MFM/RLL data recovery

[Jules Richardson]

On Mon, 2005-04-04 at 19:00 -0500, Randy McLaughlin wrote:
> From: "Vintage Computer Festival" <vcf at siconic.com>
> Sent: Monday, April 04, 2005 6:14 PM
> > On Mon, 4 Apr 2005, Randy McLaughlin wrote:
> >
> >> If you are trying to recover files you are probably wasting your time, 
> >> the
> >> XT controllers used unique formatting and you will never read the data 
> >> off
> >> of the drives without using controllers indentical with ones used
> >> originally.  It is not good enough to use the same brand or even chipset.
> >
> > This doesn't make much sense.  Can you please explain further?
> >
>
> With Vintage as a domain name you should be familiar with the fact that 
> standards develop slowly.
> 
> Hard drive interfaces for the PC "standardized" with the AT, before that 
> people did what ever they wanted.  Sometimes one controller would read a 
> disk from a different type of controller but it was just luck.

I was confused by the statement too. Are you saying that the same
*model* of controller won't necessarily work (due to different
tolerances in components say) - or just that different controllers that
happen to use a few common chips won't work?

The former would be a little alarming - the latter makes much more sense
and would seem like a given. (Maybe that's where Sellam was getting
confused?)


cheers

Jules