Section 5
SCSI
ProQ,amminQ
Guidelines
HANDLING
OF
DEFECTS
FIELDS:
TRACKS PER ZONE (Byte 2·3) - Indicates the number
of
tracks
per
defect zone on the
ProDri~e.
The
default value is six. This value is the only changeable field in page
3H'
A change
in zone size will be effective after the FORMAT
UNIT command is executed.
ALTERNATE SECTORS PER ZONE (Bytes 4.5) - Indicates
that
the
ProDri~e
will
deallocate one sector per zone from the initiator addressable blocks during
the FORMAT UNIT
comm~d.
These sectors will
be
available as replaceable sectors for defective sectors.
ALTERNATE TRACKS PER ZONE (Bytes 6·7) - Set to zero; the
ProDri~e
does not
allocate alternate tracks.
ALTERNATE TRACKS PER VOLUME (Bytes 8-9) - Set
to
zero; the
ProDri~e
does not
allocate alternate tracks.
TRACK
FORMAT
FIELD:
SECTORS PER TRACK (Bytes 10-11) - Indicates the number
of
physical sectors the
ProDri~e
allocates per disk track.
The
value
of
zero indicates that the
ProDri~e
has a variable
number
of
sectors per track (28
or
35).
SECTOR
FORMAT
FIELDS:
DATA BYTES PER PHYSICAL SECTOR (Bytes 12-13) - Indicates the number
of
data
bytes the
ProDri~e
will allocate
per
physical sector. This value may. be different than the logical
block size in the block descriptor section
of
the MODE SELECT data.
This
implies that the
ProDri~e
set an equal number
of
sectors per track accordingly. The
ProDri~e
has 512 data bytes
per
physical sector.
INTERLEAVE (Bytes 14·15) -
The
ProDri~e
has an interleave factor
of
one.
TRACK SKEW FACTOR (Bytes 16·17) - Indicates the number
of
physical sectors between
the last logical block
of
one track and the first logical block on the next sequential track
of
the same
cylinder. This field is set to 7 for the
ProDri~e.
CYLINDER SKEW FACTOR (Bytes 18-19) -Indicates the
number
of
physical sectors
between the last logical block
of
one cylinder and the first logical block on the next sequential
cylinder. This field is set to15 for the
ProDri~e.
SSEC - SOFT SECTOR (Byte 20, Bit
7)
- Always set
to
one
for
the
ProDri~e,
indicating
that it uses soft-sector formatting.
HSEC • HARD SECTOR (Byte 20, Bit
6)
- Always set
to
zero, indicating that the
ProDrive does not use hard sector formatting.
The
HSEC and SSEC bits
are
mutually exclusive.
RMB - REMOVABLE (Byte 20, Bit 5) -
Set
to
zero for the
ProDri~e,
indicating that the
10gica1
unit is not removable.
SURF - SURFACE (Byte 20, Bit
4)
-
Set
to zero to indicate that the
ProDri~e
will
allocate
progressive addresses
to
all sectors within a cylinder prior to allocating sector addresses to the next
cylinder.
INHIBIT SAVE (INS) (Byte 20, Bit 3) -
Set
to
zero
to
indicate that the ProDrive will save
the parameters
of
the page defined by Page Code
4H
as a read only page.
SCSI
Programming
Guidelines
5-49
To Next Page
Loading...