146 Product Manual - Disc Drive SCSI-2/SCSI-3 Interface (Vol. 2; Ver. 2), Rev. E
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[1] The Sense Data Length specifies the length in bytes of the following Mode Sense data that is available to
be transferred during the Data In phase. The Sense Data Length does not include itself.
[2] The disc drive supports only 00h (default medium) in the Medium Type field.
[3] A Write Protect (WP) bit of zero indicates the medium is write enabled. A WP bit of one indicates the
medium is write protected.
[4] The Block Descriptor Length specifies the length in bytes of the Block Descriptor. It is equal to the
number of bytes in the Block Descriptor (8) and does not include the page headers and mode param-
eters, if any. The disc drive sends one Block Descriptor.
Each Block Descriptor specifies the medium characteristics for all or part of a logical unit. Each Block
Descriptor contains a Density Code, a Number of Blocks, and a Block Length.
[5] The disc drive supports only 00h (default density) in the Density Code field.
[6] The Number of Blocks field specifies the number of logical blocks of the medium that meets the Density
Code and Block Length in the Block Descriptor. A Number of Blocks of zero indicates that all of the
remaining logical blocks of the logical unit have the medium characteristics specified by the Block De-
scriptor. The disc drive always returns zeros in the Number of Blocks field.
[7] The Block Length, as defined after a format function, specifies the length in bytes of each logical block
described by the Block Descriptor. Default is 512 if no Mode Select command is received before the
Format command. The usual valid values are 256 through 4096. Some disc drive products can format
down to 180 bytes per sector. Some products can only format an even numbered value of bytes per
sector (180 - 4096).
[8] When used with the Mode Sense command, a DPOFUA bit of zero indicates that the target does not
contain a cache memory or does not support the DPO and FUA bits. A DPOFUA bit of one indicates that
the target supports the DPO and FUA bits.