On Mon, 1 Nov 2010, Chuck Guzis wrote:
  On 31 Oct 2010 at 16:03, Steven Hirsch wrote:
  Ok, but I still need to know the procedure and
appropriate utility to
 surface-test the drives.  The mapping you describe appears to be a
 low-level notion that is not mapped to anything in DOS fdisk and/or
 Spinrite. 
 Have you tried installing Spinrite's DDO?  That could get you there
 regardless of what the native BIOS says.  I don't recall if this will
 work on MFM drives or not. 
I don't know what 'DDO' is, unfortunately.
  My point was that your PCs BIOS probably doesn't
know about the
 borrowed cylinder bits dodge--and your controller doesn't have its
 own BIOS on-board.
 You could also look around for a controller with its own BIOS to
 support large MFM drives--they weren't terribly uncommon. 
Apparently.  I've never seen such a thing for MFM drives.
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