Date   : Tue, 28 Feb 1984 2350 :00EST (Tuesday)
From   : George.Wood@cmu-cs-a
Subject: Re: disk editor wanted for cpm/1791

Ward Christiansen's DUU (DU version 77 ?)  is a good disk editor, but
will not do exactly what Bob Meier wants, i.e.  read a bad sector, if
the sector crc is bad; This is bacause the 179x series won't do the
read -- it reports the crc error instead.  If the sector is damaged but 
contains a valid crc, or is intermitently readable DUU will read it.

       The only way I know of to read really bad sectors is to read
the whole track and pick the sector out of the track.  I don't know of
any editor which will do this, although I have a little program which
will read a track into a buffer and let me mess with it via ddt.
Reading whole tracks is pretty hardware specific, and on some non-dma
systems, can't be done because of timing problems.

                                               George