Illustrate the technique to test the data bus.

•It is used to check data bus wiring.
•In this test we need to confirm that the received data is same as the data sent by processor.
•We use walking 1's test technique to test data bus.

Walking 1's test:
1.This test is used to independently test every bit.

2.To perform the walking 1's test, simply write the first data value in the table, verify it by reading it back, write the second value, verify, etc.

3.When you reach the end of the table, the test is complete.

4.It is okay to do the read immediately after the corresponding write this time because we are not yet looking for missing chips.

5.In fact, this test provides meaningful results even if the memory chips are not installed.

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