A nonvolatile memory device includes multiple independent nonvolatile memory arrays that concurrently for parallel reading and writing the nonvolatile memory arrays. A serial interface communicates commands, address, device status, and data between a master device and nonvolatile memory arrays for concurrently reading and writing of the nonvolatile memory arrays and sub-arrays. Data is transferred on the serial interface at the rising edge and the falling edge of the synchronizing clock. The serial interface transmits a command code and an address code from a master device and transfers a data code between the master device and the nonvolatile memory device, wherein the data code has a length that is determined by the command code and a location determined by the address code. Reading one nonvolatile memory array may be interrupted for reading another. One reading operation has two sub-addresses with one transferred prior to a command.