Seagate 100516226 Computer Drive User Manual


 
CHEETAH 15K.7 SAS PRODUCT MANUAL, REV. F 15
The current algorithm implements two temperature trip points. The first trip point is set at 68°C which is the maximum
temperature limit according to the drive specification. The second trip point is user-selectable using the Log Select
command. The reference temperature parameter in the temperature log page (see Table 2) can be used to set this trip point.
The default value for this drive is 68°C, however, you can set it to any value in the range of 0 to 68°C. If you specify a
temperature greater than 68°C in this field, the temperature is rounded down to 68°C. A sense code is sent to the host to
indicate the rounding of the parameter field.
5.2.6 Drive Self Test (DST)
Drive Self Test (DST) is a technology designed to recognize drive fault conditions that qualify the drive as a failed unit. DST
validates the functionality of the drive at a system level.
There are two test coverage options implemented in DST:
1. Extended test
2. Short test
The most thorough option is the extended test that performs various tests on the drive and scans every logical block address
(LBA) of the drive. The short test is time-restricted and limited in length—it does not scan the entire media surface, but does
some fundamental tests and scans portions of the media.
If DST encounters an error during either of these tests, it reports a fault condition. If the drive fails the test, remove it from
service and return it to Seagate for service.
5.2.6.1 DST failure definition
The drive will present a “diagnostic failed” condition through the self-tests results value of the diagnostic log page if a
functional failure is encountered during DST. The channel and servo parameters are not modified to test the drive more
stringently, and the number of retries are not reduced. All retries and recovery processes are enabled during the test. If data
is recoverable, no failure condition will be reported regardless of the number of retries required to recover the data.
The following conditions are considered DST failure conditions:
Seek error after retries are exhausted
Track-follow error after retries are exhausted
Read error after retries are exhausted
Write error after retries are exhausted
Recovered errors will not be reported as diagnostic failures.
Table 2 Temperature Log Page (0Dh)
Parameter Code Description
0000h
Primary Temperature
0001h
Reference Temperature