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Tests and Diagnostics
3.35.6.6Hard Disk Test
1) Sequential read
This subtest performs a forward read operation (0 to Maximum) by 63 sectors.
2) Address uniqueness
This subtest writes unique address data to each sector of the HDD
▼Forward sequential
▼Reverse sequential
▼Random
3) Random address / data
This subtest writes random data in a random length to random addresses. This data is then read and compared to the original data.
4) Cross talk & peak shift
This subtest writes eight types of worst pattern data (listed below) to a cylinder, then reads the data while moving from cylinder to cylinder. (Test the data interference in the neighbor track)
Worst pattern data | Cylinder |
‘ B5ADAD ‘ | 0 cylinder |
‘ 4A5252 ‘ | 1 cylinder |
‘ EB6DB6 ‘ | 2 cylinder |
‘ 149249 ‘ | 3 cylinder |
‘ 63B63B ‘ | 4 cylinder |
‘ 9C49C4 ‘ | 5 cylinder |
‘ 2DB6DB ‘ | 6 cylinder |
‘ D24924 ‘ | 7 cylinder |
PORTEGE M780 Maintenance Manual | [CONFIDENTIAL] |