Quantum Instruments DLT 7000 Cassette Player User Manual


 
SCSI Commands
Quantum DLT 7000 Tape System 5-139
READ POSITION Command (34h) (continued)
Table 5–66 READ POSITION Data - Field Descriptions
Field Name Description
BOP Beginning of Partition. When set to 1, indicates that the logical unit is
at the beginning of partition in the current partition. When 0,
indicates that the current logical position is not at the beginning of
partition. Since the tape drive does not support more than one
partition, the value of this field will be 1 when at BOT.
EOP End of Partition. When set to 1, indicates that the logical unit is
positioned between early warning and the end of partition in the
current partition. When 0, it indicates that the current logical position
is not between early warning and end of partition.
BPU Block Partition Unknown. This bit is never set: the setting of the Block
Type (BT) bit of READ POSITION CDB does not affect the block address
values returned.
First Block Location The block address associated with the current logical position: the
next block to be transferred between the target and initiator if a READ
or WRITE command is issued.
Last Block Location The block address associated with the current physical position: the
next block to be transferred to tape medium and from the target’s
buffer. If the buffer is empty, or has only a partial block, the same
value as First Block Location is reported. The first block or filemark
written onto the tape medium is at address 0.
Number of Bytes in Buffer The number of data blocks in the target’s buffer.
Number of Bytes in Buffer The number of data bytes in the buffer that have not been written to
the tape medium.