User`s guide

Bootrom Diagnostics B-3
Memory Test Description
On the first pass of the memory test, all memory is written with a
checkerboard pattern of number 5(s) and letter A(s). For example, location 0
is written as:
0x5555555
location 1 is written as:
0xAAAAAAA
location 2 is written as:
0x5555555
and so on, until all memory locations are included in the test. The processor
reads each location and verifies the data.
Memory Test Pass Two
The second pass of the test begins writing the memory with the complement
of the data taken in the first pass. For example, location 0 acquires
0xAAAAAAA, location 1 acquires 0x5555555, and so on.
Memory Test Pass Three
Pass Three of the memory test writes a unique value to each location in
memory. Location 0 is written with 0x69782534. Each subsequent location is
written with a value of decimal 105 greater than the preceding location.
When writing is completed, the processor reads each location and verifies the
data.
Memory Test Pass Four
The final pass writes all memory with zeros in preparation for loading the
system image, and verifies that all locations are, in fact, zero.
The LED walks from bit positions 0 through 4 three times before positioning
5 and 6 light only once as each test completes.