Read leveling of memory units designed to receive access requests in a sequential chained topology writing a data pattern to the memory array. In an embodiment, a memory controller first writes a desired pattern into the memory array of a memory unit and then iteratively determines the accurate calibrated delay by setting a compensation delay to a test value, reading a data portion from the memory array based on the test value for the compensation delay, comparing the data portion with an expected data, determining that the test value is a calibrated compensation delay for the memory unit if the data portion equals the expected value.