124 Product Manual - Disc Drive SCSI-2/SCSI-3 Interface (Vol. 2; Ver. 2), Rev. E
_______________________________________________________________________________________
Notes.
[1] The LUN must be zero.
[2] A Format Data (FmtData) bit of one indicates that the Format Unit Parameter list (Table 5.2.1-5a) is
supplied during the Data Out phase. The Data Out phase consists of a defect list header (Table 5.2.1-5b),
followed by an initialization pattern descriptor (Table 5.2.1-6a) (if any) followed by the defect descriptors.
The format of the defect descriptor list is determined by the Defect List Format field. A FmtData bit of zero
indicates the Data Out phase shall not occur (no defect data shall be supplied by the initiator).
A Complete List (CmpLst) bit of one indicates the data supplied is to be the complete list of Growth
defects. Any previous Growth defect data or Certification defect data shall be erased. The disc drive may
add to this list as it formats the medium. The result is to purge any previous Growth or Certification defect
list and to build a new defect list. A CmpLst bit of zero indicates the data supplied is in addition to the
existing Growth defect list.
The use of the P list and C list defect is controlled by byte 1 of the defect list header (see Table 5.2.1-5b).
The Defect List Format field specifies additional information related to the defect list. (See Table 5.2.1-4
for further information.)
[3] The Interleave field requests that logical blocks be related in a specific fashion to the physical blocks to
facilitate data transfer speed matching. An interleave value of zero requests that the target use its default
interleave. An interleave value of one requests that consecutive logical blocks be placed in consecutive
physical order. Values of two or greater indicate that one or more (respectively) physical blocks separate
consecutive logical blocks. The disc drive implements an optional prefetch (“read look ahead”) function
which reads a user-specified number of sectors into its buffer beyond and contiguous to the sectors
requested by the read command. This data is subsequently available for the next sequential read com-
mand without re-access of the disc media thereby increasing performance and negating the need for an
interleave during format if this prefetch option is enabled. (See Read Command, Section 5.2.1.4.) Inter-
leave values other than zero or one are vendor specific.
[4] See “Control Byte” paragraph 4.2.6.
The following definitions of flaw categories are supplied to help in understanding the alternatives listed in
Table 5.2.1-4.
P = Primary Defect Type: P type flawed sectors are identified at the time of shipment in a list of defects
(permanent flaws) supplied by Seagate and stored on the disc in an area that is not directly accessible by
the user. (This list may be referred to as an ETF List). This defect list is not modified or changed by the
disc drive (or initiator) after shipment.
C = Certification Defect Type: C type flawed sectors are sectors that fail a format verify during the format
function.
D = Data Defect Type: D type sectors are sectors identified in a list supplied to the target by the initiator
during a Data Out phase of the current Format Unit command. The D List follows a four byte defect list
header and is referred to as Defect Descriptor Bytes.
G = Growth Defect Type: G type flawed sectors contain medium flaws and have been reallocated as a result
of receiving a Reassign Blocks command, or certification defects (C type) reallocated during a previous
Format Unit command, or Data Defects (D type) reallocated during a previous Format Unit command or
defects that have been automatically reallocated by the drive. This (G) list is recorded on the disc drive
media and may be referenced for the current (and subsequent) Format Unit commands. This (G) list
does not include the Primary (P) list of defects.
