HP Surestore 80fx Optical Drive and Library SCSI-2 Command Reference - Page 70

SCSI-2 Drive Commands Table 2-28 Table 2-29 NOTE SCSI-2 Drive Command Set Mode Select Command (15H) Mode Select Header Mode Select Header Byte 7 6 5 4 3 2 1 0 0 Reserved (0) 1 Medium Type 2 Reserved (0) 3 Block Descriptor Length The Medium Type field shall be set to 00H (Default, only one medium type supported), 02H (Write-once medium), or 03H (Optical Reversible or Erasable medium). The Block Descriptor Length specifies the length in bytes of the block descriptor. It shall be equal to 0 or 8. A Block Descriptor Length of zero indicates that the block descriptor is not included in the parameter list. This condition is not considered to be an error. Mode Select Block Descriptor Byte 7 6 5 4 3 2 1 0 0 Density Code 1 Number of Blocks (MSByte) 2 Number of Blocks 3 Number of Blocks (LSByte) 4 Reserved (0) 5 Block Length (MSByte) 6 Block Length 7 Block Length (LSByte) All fields in the Block Descriptor have no effect on the drive. Chapter 2 2-33