Imaging DEC uVAX MFM drives

Roy J. Tellason rtellason at
Wed Aug 30 12:21:59 CDT 2006

On Tuesday 29 August 2006 05:04 pm, Chuck Guzis wrote:
> On 8/29/2006 at 1:47 PM Zane H. Healy wrote:
> >I suspect, but this is only a guess, that the issue is the way the DEC MFM
> >drives are formated.  There are only two ways that I'm aware of to format
> >an MFM drive for use on a VAX.  One is with a MicroVAX/VAXstation 2000
> >(formatter is built into the ROM's), the other is with the Field Service
> >Diagnostics (customer diagnostics can't format drives).
> Bingo.  Even back in the old PC XT/AT MFM days, you couldn't always take an
> MFM drive formatted on one manufacturer's controller and use it as-is on
> another's.

I also remember some instances where you couldn't replace a failed controller 
with another one of the same brand,  but of a different model.  And sometimes 
even if they were the same model,  but different "BIOS" (?) or other software 
revisions would screw things up.

Why was that?

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ablest -- form of life in this section of space,  a critter that can
be killed but can't be tamed.  --Robert A. Heinlein, "The Puppet Masters"
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M Dakin

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