Quantum DLT 2500, Product Manual

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DLT2000 SCSI Interface
8-32 DLT2000/DLT2700 Cartridge Tape Subsystem
Parameter
Code
Description
00h
01h
02h
03h
04h
05h
06h
8000h Errors corrected with substantial delays
Errors corrected with possible delays
Total rewrites or rereads
Total errors corrected
Total times correction algorithm processed
Total bytes processed
Total uncorrected errors
Vendor Unique
Figure 8-16 Parameter Codes Supported
Parameter codes 00h, 01h, and 04h will always return a value of zero.
__________________________Note _____________________________
Parameter value for code 05h will be 8 bytes; the parameter length will be set
to 8.
____________________________________________________________
Byte 2 of Log parameter block in Figure 8-15 is referred to as the parameter control
byte.
•
DU–Disable Update: DU bit is not defined for LOG SELECT and the target shall
ignore any value.
•
DS and TSD–Saving parameters is not supported; they both should be set to 1. If
the DS and/or TSD are set to zero, the command is terminated with CHECK
CONDITION status with the sense key set to ILLEGAL REQUEST with the
additional sense code set to INVALID FIELD IN PARAMETER LIST.
•
ETC–Enable Threshold Comparison: When set to 1, the drive will perform a
comparison with threshold values once the cumulative value is updated.
Comparison criteria is defined in TMC. If the comparison is met and the RLEC bit
of MODE SELECT/SENSE Control Page is set to 1, then a UNIT ATTENTION
is
generated for all initiators. The additional sense code is set to LOG EXCEPTION
and the additional sense code qualifier is set to THRESHOLD CONDITION MET.
If the RLEC bit is zero and the comparison is met, then UNIT ATTENTION
is not
generated.
•
TMC–Threshold Met Criteria: See Figure 8-23 for the list of criteria. Once the
specified criteria in this field is met and the ETC bit is 1 and the RLEC bit in
MODE SENSE/SELECT Control Page is set to 1, then UNIT ATTENTION is
generated for all initiators.