Toshiba L20 Laptop User Manual


 
Test Program for Field.
Satellite L20 Maintenance Manual(960-Q01) 129
3.14 MEMORY2 Test
To execute the Expansion Test select 11 from the Diagnostic Test Menu, press Enter and
follow the directions on the screen. The MEMORY2 Test contains four subtests that test the
computer's. Move the highlight bar to the subtest you want to execute and press Enter.
NOTE: If NO is selected for Test Loop on the Test Parameter menu, the Test Status
screen displays while the test is executing. When the test is complete the Memory Test
menu displays.
If YES is selected for Test Loop on the Test Parameter menu, the Test Status screen
displays while the test is executing. Press Ctrl + break to return to the Memory Test menu
Subtest 01 All one/All zero test
This subtest performs pseudorandom data read/write. The data consists of “all
ones”/”all zero” patterns produced by pseudorandom sequence generator. The
test checks address error.
FFFFFFFFFFFFFFFF0000000000000000
0000000000000000FFFFFFFFFFFFFFFF
Subtest 02 Walking 1/Walking 0 test (Left)
This subtest uses “running one”/”running zero” patterns. This test sequence
allows also to checking system bus in maximum noise conditions. The
following test sequence is written.
7FFF7FFF7FFF7FFF8000800080008000
BFFFBFFFBFFFBFFF4000400040004000
After all the memory being tested is filled with the pattern, it is read in
descanting direction and compared with reference data. As the memory is
read, the data is replaced with inverse test pattern. After all the memory is
read and replaced with inverted pattern, it is read in descanting direction and
compare with new reference data. As the memory is read, the data is replaced
with next pattern, which is like first one shifted to right.
Subtest 03 Walking 1/Walking 0 test (Right)
Tee test method is the same as Subtest2. However, the data to be used differs.
80008000800080007FFF7FFF7FFF7FFF
4000400040004000BFFFBFFFBFFFBFFF
Subtest 04 Walking 1/Walking 0 test (Left/ Right)