Reference Guide

Chapter 4 SCSI Commands
MODE SELECT (6) / (10) Command (15h / 55h)
DLT-S4 Interface Reference Guide 119
Table 72 Device Configuration
MODE SELECT Page — Field
Descriptions
Field Description
PS Parameters Savable. For
MODE SELECT, must be set to 0.
SPF SubPage Format. Always set to 0. Indicates that this page uses the page_0 page
format.
Page Code Identifies the type of
MODE SELECT page being transferred. A value of 10h
identifies this as the Device Configuration Page.
Page Length Indicates the number bytes in the page, excluding bytes 0 and 1. The length is
returned in
MODE SENSE commands and must subsequently be set to the same
value when performing
MODE SELECT.
CAF Change Active Format. Must be set to 0.
Active Format Must be set to 0.
Active Partition The drive only supports partition 0.
Write Buffer Full
Ratio
The drive sets this field to 0. The drive uses an automatic adaptive mechanism
to adjust its Write Buffer Full Ratio according to the average data rates over the
SCSI bus.
Read Buffer Empty
Ratio
The drive sets this field to 0. The drive uses an automatic adaptive mechanism
to adjust its Read Buffer Empty Ratio according to the average data rates over
the SCSI bus.
Write Delay Time Indicates the maximum time, in 100 ms increments, that the drive waits with a
partially full buffer before forcing the data to tape. The buffer Full / Empty
ratio, which is dynamic, can cause data to be written sooner than the Write
Delay Time would indicate. The Write Delay Time defaults to 100 (64h). This
causes the drive to flush the buffer in 10 seconds. The maximum value is 6500
(1964h); the minimum value is 15 (0Fh), representing a range from 11 minutes to
1.5 seconds. A value of 0 disables forcing data to tape based on time in the
buffer. The drive rounds values greater than 6500 down to 6500.
DBR Data Buffer Recovery. Must be set to 0.
BIS Block Identifiers Supported. This bit is supported and must be set to 1.
RSmk Report Setmark. Must be set to 0.
AVC Automatic Velocity Control. Must be set to 0.