User Manual
SCSI Commands Reference Manual, Rev. J 84
www.seagate.com Direct Access Block commands (SPC-5 and SBC-4)
3.3.5.5 Long block format address descriptor
A format type of 011b specifies the long block format address descriptor defined in table 48.
LONG BLOCK ADDRESS field
For the FORMAT UNIT command, the LONG BLOCK ADDRESS field contains the eight-byte logical block address of a defect. If multiple logical
blocks are contained within a physical block, then the device server may consider logical blocks in addition to the one specified by this descrip-
tor as containing defects. For the READ DEFECT DATA commands, the LONG BLOCK ADDRESS field contains a vendor-specific eight-byte value.
For the Translate Address diagnostic pages, the LONG BLOCK ADDRESS field contains a four-byte LBA or a vendor-specific four byte value that
is greater than the capacity of the medium.
3.3.5.6 Bytes from index format address descriptor
A format type of 100b specifies the bytes from index address descriptor defined in table 49. For the FORMAT UNIT command and
the READ DEFECT DATA commands, this descriptor specifies the location of a defect that is either the length of one track or is no
more than eight bytes long. For the Translate Address diagnostic pages, this descriptor specifies the location of a track or the first
byte or last byte of an area.
CYLINDER NUMBER field
The CYLINDER NUMBER field contains the cylinder number.
HEAD NUMBER field
The HEAD NUMBER field contains the head number.
BYTES FROM INDEX field
The BYTES FROM INDEX field contains the number of bytes from the index (e.g., from the start of the track) to the location being described. A
BYTES FROM INDEX field set to FFFFFFFFh specifies that the entire track is being described.
For sorting bytes from index format address descriptors, the cylinder number is the most significant part of the address and the bytes from
index is the least significant part of the address. More than one logical block may be described by this descriptor.
Table 48 Long block format address descriptor (011b)
Bit
Byte
7 6 5 4 3 2 1 0
0
(MSB)
LONG BLOCK ADDRESS
. . .
7
(LSB)
Table 49 Bytes from index format address descriptor (100b)
Bit
Byte
7 6 5 4 3 2 1 0
0
(MSB)
CYLINDER NUMBER
. . .
2
(LSB)
3
HEAD NUMBER
4
(MSB)
BYTES FROM INDEX
. . .
7
(LSB)