Quantum DLT 4000 Manual descarregar pdf (Página 146)

SCSI Commands

5-46 Quantum DLT 4000 Tape Drive

LOG SENSE Command (4Dh) (continued)

Table 5–21 Log Parameters for Read / Write Error LOG SENSE Page Field Descriptions

(continued)

Field Name Description

Parameter Code

(continued)

8000h - Vendor Unique

Note: Parameter codes 00h, 01h, and 04h always return a value of 0. Parameter

value for 05h is 8 bytes; the parameter length is set to 8.

DU Disable Update. This field with a value 0 indicates that the target will update all

log parameter values. This field set to 1 indicates that the 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 to 1 if

the host set the bit in the last LOG SELECT command. Default is 0.

Note that for parameter types other than threshold and cumulative values, this

bit is always 0.

DS Disable Save. Not supported; always set to 1.

TSD Target Save Disable. Not supported; always set to 1.

ETC Enable Threshold Comparison. When set to 1, indicates that comparison to

threshold is performed. ETC of 0 indicates that the comparison is not performed.

This bit is set to 1 by MODE SELECT. Default is 0.

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 using LOG SELECT. If the result

of comparison is true (cumulative = threshold), and MODE SELECT / SENSE

CONTROL MODE page RLEC bit is set to 1, then a UNIT ATTENTION is granted for

all initiators. The sense key is set to UNIT ATTENTION, the additional sense code

to LOG EXCEPTION, and ASCQ is set to THRESHOLD CONDITION MET. If the RLEC

bit in CONTROL MODE page is 0, then UNIT ATTENTION is not generated.

Note that comparison is performed in real time. A Log Sense command need

not be issued to get the CHECK CONDITION. Once ETC is selected, RLEC bit in

control mode page, the CHECK CONDITION is issued based on the criteria

defined in the TMC bits if the criteria are met in real time. CHECK CONDITION will

not identify for which parameter code the criteria is met. Log Sense must be

issued to read the counters to determine for which parameter code criteria has

been met.

1 2 ... 141 142 143 144 145 146 147 148 149 150 151 ... 299 300

Sem comentários

Quantum DLT 4000 Manual Página 146