In one embodiment, the data storage apparatus includes a control unit configured to decode at least one input command and configured to generate at least one of a read signal and a start signal in response to the input command. The start signal indicates to start an internal mode determination process. The data storage apparatus also includes a memory unit configured to output data in response to the read signal, and a coding unit configured to start and perform the internal mode determination process in response to the start signal. The internal mode determination process includes autonomously determining a coding mode, and the coding unit is configured to code the output data based on the determined coding mode to produce coded data.