Fujitsu M2488 manual LOG Sense command 4Dh, LOG Sense CDB Description, LOG Sense Field Description

M2488 PRODUCT GUIDE TAPE UNIT SCSI COMMANDS

4-3.10 LOG SENSE command 4Dh

The LOG SENSE Command provides a means for the initiator to retrieve statistical information maintained by the target about itself and attached logical units. It is a complementary command to the LOG SELECT command. Log data is collected within the target on a per event basis regardless of the initiator ID.

4-3.10.1 LOG SENSE CDB Description

LOG SENSE is a ten-byte command. The bytes are shown below and described in Table 4-34. 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	1	0		0		1		1	0		1
1
		LUN					Reserved			PPC=0b		0
2
	PC=01b							Page Code
3						Reserved
4						Reserved
5	MSB				Parameter Pointer
6													LSB
7	MSB				Allocation Length
8													LSB
9				Reserved							Flag		Link

Note: Changeable fields in the CDB are shaded.

Table 4-30. LOG SENSE Field Description

BYTE	BIT	VALUE	DESCRIPTION
0	0-7	4Dh	Operation code.
1	1	0b	The Parameter Pointer Control (PPC) bit controls the type of parameters
			requested from the target. The PPC bit must be zero indicating that the log
			parameter requested from the target shall begin with the parameter code specified
			in the Parameter Pointer field and return the number of bytes specified by the
			Allocation Length field in ascending order of parameter codes from the specified
			log page. A PPC bit of zero and a Parameter Pointer field of zero shall cause all
			available log parameters for the specified log page to be returned to the initiator
			subject to the specified allocation length.
2	0-5		The Page Code field identifies which page of data is being requested. The page
			codes are described in Table 4-31.
2	6-7	01b	A Page Control field (PC) of 01b must be specified to indicate that the target’s
			current cumulative counter values for the specified log pages are returned.

April 1997 CG00000-011503 REV. A 4-33