Quantum DLT1/VS80 SCSI, Interface Manual

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Chapter 4: SCSI Commands
4-94 July 2004 81-81276-01 Rev A01
4.16 RECEIVE DIAGNOSTICS RESULTS (1Ch)
The RECEIVE DIAGNOSTIC RESULTS command tells the tape drive to send analysis data to the
initiator after completing a SEND DIAGNOSTIC command. The tape drive returns the following data
as a result of this command. A REQUEST SENSE command should be issued to obtain more detailed
information following a CHECK CONDITION on a SEND DIAGNOSTIC command.
Figure 4-65.
RECEIVE DIAGNOSTICS RESULTS (1Ch) Command Descriptor Block — Data
Format
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 the media and from the target's buffer. If the buffer is empty, or
has only a partial block, the tape drive reports the same value as First Block
Location. The first block or filemark written onto the media is at address 0.
Number of Blocks 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 medium.
Bit
Byte
7 6 5 4 3 2 1 0
0 Operation Code (1Ch)
1 Logical Unit Number Reserved
2 Reserved
3 - 4
(MSB)
Allocation Length
(LSB)
5 Unused Reserved Flag Link
Table 4-56.
READ POSITION (Short Format) — Field Descriptions (Continued)
Field Name Description