IBM xSeries 380, Hardware Maintenance Manual

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Diagnostics
25
Pattern Test The test order is:
Select Memory from the Main Menu, Pattern Test, and press <Enter>. A list of
parameters appears:
You can specify the beginning and ending memory locations in the Memory Start and
Memory End fields. You can also specify the size of the bit pattern written to memory
in the Pattern Size field. By changing the bit pattern size, otherwise undetected
memory errors can be discovered. Change this parameter to ALL to perform the most
thorough memory error detection test.
Bit Pattern Sizes: The bit pattern sizes are 8 bits, 16 bits, 32 bits, or all bit pattern
sizes. The default is 32 bits. If the displayed percentage is less than 100%, the specified
percentage is the amount of system memory between the Memory Start and Memory
End values that has been tested. If no errors occur, select Return to main menu when
this test finishes. Select Browse error list if errors occur.
Extended pattern test
This test is composed of two test routines that write data to memory, read the data
back and compare the data. The subtests repeat until you press <Esc>. They are:
Test Name Description
Bit Stuck High test Searches for bits stuck high.
Bit Stuck Low test Searches for bits stuck low.
Checkerboard test Write bit patterns successively to non-contiguous
memory areas.
CAS Line test Tests the Column Address Strobe signal line.
Incremental test Tests memory by writing incremental patterns and
reading them.
Decremental test Tests memory by writing decremental patterns and
reading them.
Incremental Decremental test Tests memory by writing incremental and
decremental patterns and reading them back.
Run the Test