Quantum DLT 4700, Руководство по эксплуатации продукта

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DLT4000 SCSI Interface
DLT4000/DLT4500/DLT4700 Cartridge Tape Subsystem 8-39
Parameter Code
The following parameter codes are supported for the read/write error counter pages.
Parameter
Code
Description
00h Errors corrected with substantial delays
01h Errors corrected with possible delays
02h Total rewrites or rereads
03h Total errors corrected
04h Total times correction algorithm processed
05h Total bytes processed
06h Tortal uncorrected errors
8000h Vendor Unique
Figure 8-22 Parameter Codes Supported
Parameter codes 00h, 01h, and 04h will always return a value of zero.
DU, DS, TSD, ETC, TMC, and LP are collectively referred to as parameter control
byte.
•
DU–Disable Update: A zero value indicates that target updates all log parameter
values. A value of 1 indicates that target will not update the log parameter values
except in response to LOG SELECT. This bit is set by the drive when
accumulated values reach maximum. This is also returned set if the host set the
bit in the last LOG SELECT command. The default is zero.
_________________________ NOTE ____________________________
For parameter types other than threshold and cumulative values, this bit is
always zero.
•
DS–Disable Save: Saving parameters is not supported; this bit will always be set
to 1.
•
TSD–Target Save Disable: Saving parameters is not supported; this bit will
always be set to 1.
•
ETC–Enable Threshold Comparison: ETC of 1 indicates that comparison to
threshold is performed. ETC of zero indicates that this comparison is not
performed. This bit is set to 1 by MODE SELECT. Default is zero.
•
TMC–Threshold Met Criteria: This field is valid only if host sets ETC to 1. It
determines the basis for comparison and is specified by host by LOG SELECT. If
the result of comparison is true (cumulative = threshold) and MODE
SELECT/SENSE control mode page RLEC bit is set 1, then a unit attention is
generated for all initiators. The sense key will be set to UNIT ATTENTION, ASC