Sony SDX-800V/R manual Device Configuration Page 10h, Device Configuration Bit Byte, Cap, Rew, Sew

6.Command Specification MODE SELECT

6.7.4. Device Configuration Page (10h)

The drive supports the Device Configuration Page which has the following format:

Table 6-42: Device Configuration Page

Bit	7	6	5		4	3	2	1	0
Byte
0	PS (0)	Reserved				Page Code (10h)
1					Page Length (0Eh)
2	Reserved	CAP	CAF (0)				Reserved
3					Active Partition
4				Write Buffer Full Ratio (00h)
5			Read Buffer Empty Ratio (00h)
6	(MSB)				Write Delay Time (64h)
7									(LSB)
8	DBR (0)	BIS (1)	RSmk		AVC (0)	SOCF (00b)		RBO (0)	REW
9					Gap Size (00h)
10	EOD Defined (000b)				EEG (1)	SEW		Reserved
11	(MSB)		Buffer		Size at Early Warning (00 00 00h)
12
13									(LSB)
14			Select Data Compression Algorithm (0x00)
15					Reserved

CAP: The Change Active Partition bit, when set to one, indicates that the partition is changed to the one specified by the Active Partition Field. This is a feature supported by the drive and is discussed below.

CAF: The Change Active Format bit, set to one, indicates that the active format is to be changed to that set in the Active Format Field. This field is not supported.

Active Partition: Indicates the current partition number in use on the medium.

Setting this field to a non-existing partition number will be rejected by the drive with a CHECK CONDITION status and the ILLEGAL REQUEST sense key set.

Write Buffer Full Ratio and Read Buffer Empty Ratio: These fields are not supported by the drive. Setting these fields to anything other than ZERO will cause the drive to return a CHECK CONDITION status and an ILLEGAL REQUEST sense key.

The drive implements an algorithm which automatically adjusts these ratios so as to maximize streaming to the Host.

Write Delay Time: This field indicates the maximum time, in 100 millisecond increments, that the drive shall wait with a partially full buffer before forcing the data to tape. The drive defaults to a 10 second delay since the last SCSI bus activity before the data is flushed from the buffer to the tape. If Write Delay Time is set to ZERO the drive will wait indefinitely for the data group to be filled.

DBR: This field is not supported and should be always set to ZERO.

BIS: Block Identifiers Supported is set to one to indicate that the media has recorded information about the logical block ID relative to the partition.

The DBR and BIS bit are only valid on a MODE SENSE command where they are used to report drive capabilities. These bits are ignored by the drive on a MODE SELECT command. The drive will not return a CHECK CONDITION.

RSmk: The Report Set Mark bit, when set to one, indicates that Set Marks will be reported to the drive. When ZERO, Set Marks are NOT reported. The default is one, Set Marks reported.

AVC: Automatic Velocity Control function is not supported by the drive and if this bit is set a CHECK CONDITION status is returned with an ILLEGAL REQUEST sense key.

SOCF: Stop on Consecutive File-marks function is not supported by the drive and if this bit is set a CHECK CONDITION status is returned with an ILLEGAL REQUEST sense key.

6-44 SONY AIT-3Ex drive SDX-800V series Ver.1.1