HP Surestore 80fx Optical Drive and Library SCSI-2 Command Reference - Page 131

SCSI-2 Drive Command Set Pre-Fetch (34H) Table 2-81 Pre-Fetch (34H) The Pre-Fetch command is used to transfer the specified number of data blocks starting from the specified logical block address to cache memory. Pre-Fetch Command Byte 7 0 1 2 3 4 5 6 7 8 9 6 5 4 3 2 1 0 Operation Code (34H) Reserved (0) Immed RelAdr Logical Block Address (MSByte) Logical Block Address Logical Block Address Logical Block Address (LSByte) Reserved (0) Transfer Length (MSByte) Transfer Length (LSByte) Reserved (0) Flag Link Immed Transfer Length Rel Adr An Immediate bit of 1 indicates that the drive returns a status as soon as the command descriptor block is validated. An Immed bit of 0 indicates that the status is not returned until the operation is completed. This field indicates the number of contiguous logical blocks of data to be transferred. A relative address bit of one indicates that logical block address specified is a two's complement offset from the last logical block address accessed. A value of 0 indicates that the logical block address is an absolute address. 2-94 Chapter 2