You didn't say exactly *what* you typed to make this happen.  But I
presume from this:

   fd0d: hard error reading fsbn 1 (st0 40<abnrml> st1 1<no_am> st2 0 cyl 0 hd 0 se

That you're trying to newfs or label partition `d'.  This is wrong.
The floppy driver used the low bits of the minor number to specify the
density.


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