


      BBBBAAAADDDDBBBBLLLLOOOOCCCCKKKKSSSS((((4444))))                 ((((RRRRiiiiddddggggeeee))))                 BBBBAAAADDDDBBBBLLLLOOOOCCCCKKKKSSSS((((4444))))



      NNNNAAAAMMMMEEEE
           badblocks - media defect list for 445-Mb disc in companion
           cabinet

      DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
           _B_a_d_b_l_o_c_k_s is the only file on the "badblocks" floppy disc
           shipped with each 445-Mb disc.

           Winchester-type discs (including all Ridge discs), come from
           the factory with a list of their own manufacturing defects.
           For the 60-Mb and 142-Mb discs in the Ridge 32 cabinet, the
           bad block table is permanently encoded on the disc and
           printed on paper in a plastic pocket that stays with the
           unit.  For the 445-Mb disc unit in the companion cabinet,
           the bad block information is distributed on a separate
           floppy disc.

           The bbbbaaaaddddbbbblllloooocccckkkkssss file on the bbbbaaaaddddbbbblllloooocccckkkkssss floppy disc describes
           the cylinder, surface (or head), byte offset from the disc
           index mark, and length of each defect.

           On ROS 3.1 and subsequent releases, the defect list is kept
           on the floppy in the following format:

                _c_y_l-_n_u_m  _h_e_a_d-_n_u_m _b_y_t_e-_o_f_f_s_e_t _l_e_n_g_t_h

           example:

                 12  4  2359  16
                104  7 12304   3
                 66  5  3412   2


           In the sad event that the system must be rebuilt, the the
           445-Mb badblocks floppy must be available.




















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