Memory system, memory access interface device and operation method thereof

The present disclosure discloses a memory access interface device. A clock generation circuit generates reference signals. A transmitter transmits an output command and address signal to a memory device according to the reference signals. A signal training circuit executes a training process in a training mode that includes steps outlined below. A training signal is generated such that the training signal is transmitted as the output command and address signal. The training signal and the data signal generated by the memory device are compared to generate a comparison result indicating whether the data signal matches the training signal. The comparison result is stored. The clock generation circuit is controlled to modify a phase of at least one of the reference signals to be one of a plurality of under-test phases to execute a new loop of the training process until all the under-test phases are trained.