Fujitsu M2488 manual Recover Buffered Data command 14h, Recover Buffered Data CDB Description

TAPE UNIT SCSI COMMANDS M2488 PRODUCT GUIDE

4-3.21 RECOVER BUFFERED DATA command 14h

RECOVER BUFFERED DATA requests that the tape unit transfer one or more blocks of data from the tape unit’s buffer to the initiator. The command is used to retrieve data contained in the buffer that had been sent earlier by the initiator to be written to the medium [tape]. The command is typi- cally used following an error condition which indicates that data could not be written to the medium [tape]. Several RECOVER BUFFERED DATA commands may be needed to retrieve all buffered write blocks.

The Information field of sense data returned for a RECOVER BUFFERED DATA command is anal- ogous to the Information field of sense data returned for a READ command. Please see the READ command description in paragraph 4-3.14 on page 4-63 for a description of this field.

4-3.21.1 RECOVER BUFFERED DATA CDB Description

RECOVER BUFFERED DATA is a six-byte command. The bytes are shown below and described in Table 4-97. Common fields are described in paragraph 4-3.1 on page 4-4.

								BITS
BYTES	7		6	5		4			3	2	1		0
0	0		0	0		1			0	1	0		0
1												SILI
			LUN						Reserved					Fixed
2
		MSB
3
							Transfer		Length
4
														LSB
5
					Reserved							Flag		Link

Note: Changeable fields in the CDB are shaded.

Table 4-97. RECOVER BUFFERED DATA Field Description

BYTE	BIT	VALUE	DESCRIPTION
0	0-7	14h	Operation Code.
1	0		The Fixed bit specifies both the meaning of the transfer length field and whether
			fixed-length or variable-length blocks are to be transferred.
			If the Fixed bit is zero, a single block is transferred with the bytes transferred being
			the lesser of the actual block length or the requested transfer length.
			If the Fixed bit is one, the transfer length specifies the number of blocks to be trans-
			ferred to the initiator.
1	1		Suppress Incorrect Length Indication (SILI) flag.
2-4			The Transfer Length indicates the number of bytes or blocks to transfer. The block
			length used is the current block length specified in the mode parameters block
			descriptor (refer to the Mode Select Block Descriptor in Table 4-47 on page 4- 53.)
			When the transfer length is zero, no data is transferred and the current position on
			the logical unit is not changed. This condition is not considered an error.

4-98 CG00000-011503 REV. A April 1997