Quantum Quantum Atlas 10K II 9.2/18.4/36.7/73.4 GB, Product Manual

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SCSI Description
Quantum Atlas 10K II Ultra160/m SCSI Hard Disk Drives 5–69
MODE SELECT (6) Command (15h) (continued)
Table 5–34 Disconnect–Reconnect) — Field Descriptions
Default
Field Value Description
PS 0 Parameters Savable. This bit is only used with the MODE SENSE
command. A returned value of 1 indicates that the target is capable
of saving the page in a non-volatile, vendor-specific location. The bit
is reserved with the MODE SELECT command.
Buffer Full Ratio 0 The Buffer Full Ratio indicates how full the buffer should be prior to
requesting an interconnect tenancy. Applies to READ operations
only. The default of 0 indicates to the drive that it should use its
default ratio.
Buffer Empty Ratio 0 The Buffer Empty Ratio indicates how full the buffer should be prior
to requesting an interconnect tenancy. Applies to READ operations
only. The default of 0 indicates to the drive that it should use its
default ratio.
Bus Inactivity Limit 0 The Bus Inactivity Limit indicates the maximum duration of any
interconnect tenancy during which no data is transferred.
Not
supported by the drive.
Disconnect Time Limit 0 The Disconnect Time Limit specifies the minimum time, in 100
microsecond increments, that the drive waits after releasing the SCSI
bus before reselecting. The drive supports a maximum value of
0xFF. Values greater than 0xFF are treated as 0xFF. The default value
of 0 indicates that the drive can reslect immediately after releasing
the bus.
Connect Time Limit 0 The Connect Time Limit indicates the maximum duration of a single
interconnect tenancy.
Not supported by the drive.
Maximum Burst Size 0 The Maximum Burst Size specifies the maximum amount of data
that the drive will transfer during a data phase before disconnecting
from the bus, assuming it was given the disconnect privilege. This
value is expressed in increments of data sectors (that is, a value of 1
indicates 512 bytes, a value of 2 indicates 1024 bytes). The default
value of 0 indicates that there is no limit on the amount of data
transferred per connection.
This field is reserved for the SCSI-
1/CCS operating mode.
EMDP 0 Enable MODIFY DATA POINTER. Not supported by the drive.
Fairness Arbitration 111b Indicates whether or not the target should use fair or unfair (e.g.,
priority) arbitration when beginning the interconnect tenancy.
Value Description
000b Disables the fairness algorithm. A fixed priority
scheme based on the SCSI ID assigned is used.
Non-Zero Any non-zero value enables the fairness algorithm
(SCSI SPI-2 ANSI standard, Appendix C).
DImm 0 Disconnect Immediate. When set to a 1, to reduce on-bus time, the
drive is forced to disconnect from the SCSI Bus after a SCSI
Command is received. Disconnect Immediate works only when a
typical, error-free command is received. Disconnect Immediate does
not apply in exception conditions (for example, SDTR received,
error, etc.).