Quantum DLTtape DLT 7000, Руководство по эксплуатации продукта

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SCSI Commands
Quantum DLT 7000 Tape System 5-83
MODE SELECT (6) / (10) Command (15h) / (55h) (continued)
Table 5–44 Device Configuration Page - Field Descriptions
Field Name Description
PS Parameters Savable. For MODE SELECT, this bit must be 0.
Additional Page Length This field indicates the number bytes in the page. However, the value
does not include 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. If the page length does not match that
expected by the drive, a CHECK CONDITION status is returned, sense key
set to ILLEGAL REQUEST.
The drive returns a CHECK CONDITION status with sense key set to
ILLEGAL REQUEST if it receives an unsupported Page Code or a Page field
with values not supported or changeable. In such cases, no parameters
are changed as a result of the command.
CAP Change Active Partition. Not supported; must be 0.
CAF Change Active Format. Not supported; must be 0.
Active Format Not supported. Must be 0.
Active Partition Only partition 0 is supported. Setting this field to any other value causes
rejection by the drive with a CHECK CONDITION status, sense key ILLEGAL
REQUEST set.
Write Buffer Full Ratio The drive sets this field to 0. The drive uses an automatic adaptive
mechanism to adjust its 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 Empty Ratio according to the average data rates
over the SCSI bus.
Write Delay Time This field indicates the maximum time that the drive will wait with a
partially full buffer before forcing the data to tape (100 ms increments).
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 200 (C8h). This causes the buffer to be flushed in 20
seconds. Maximum value is 6500 (1964h) and the minimum is 15 (0Fh).
This represents a range from 11 minutes down to 1.5 seconds.
Values between 0 and 15 on a MODE SELECT, are rounded down to 0.
This causes the data to go straight to the medium without delay.