Date   : Tue, 11 Jul 2006 23:18:44 +0100
From   : "Ian Wolstenholme" <BBCMailingList@...>
Subject: Re: Viglen Winnie / Miniscribe 3438

Yes, the ACB4000 is MFM so you can get 33 sectors per track on
the Beeb at 256 bytes per sector (17 on PC with 512 bytes per sector)
and 47 sectors per track (26 for PC) with the ACB4070.

It's a bit like the 8271 floppy controller being single density and the
1770 being double density.

The Technomatic Winchester has the same controller although it only
has an MFM drive!

So if you are using an MFM controller you really need to change the
value of the sector-bodge variable in line 1 of Superform from 47 to 33
otherwise you will find that you can't access all the sectors on the disc.

The Viglen setup sounds ideal because it's RLL controller and drive together
so with the Miniscribe drive you get 615 cylinders, 4 heads, 47 sectors
per track and 256 bytes per sector = 29,598,720 bytes or 28.22MB.  Seems
like nothing now but 20 years ago that was pretty good!

Best wishes,



Ian

----- Original Message -----
From: Joel Rowbottom
To:  Andrew Benham <adsb@...>
Cc:  bbc-micro@...
Sent:  Tue, 11 Jul 2006 23:04:43 +0100
Subject: Re: [BBC-Micro] Viglen Winnie / Miniscribe 3438

At 23:00 11/07/2006, Joel Rowbottom wrote:

>>If you have an Adaptec ACB4000 then it's easy - Acorn's SuperForm stores
>>the disk size in a hidden area of the drive.
>
>It's an ACB4000 :)

Actually, it's an ACB4070. Different?



--
Joel Rowbottom, was-kid, geek, coder, bad penny, 'Net addict since 1991
Personal: http://www.joel.co.uk | Pics: http://photos.jml.net