1. A memory card comprising: a bus; a central processing unit (CPU) connected to the bus; a volatile memory connected to the bus; a nonvolatile memory; and a host interface receiving a first command signal from a host and outputting a reset signal for resetting the CPU, receiving an update application program from the host and outputting the update application program to the volatile memory, receiving a second command signal from the host and outputting a reset release signal for releasing a reset state of the CPU, and receiving an update program from the host and outputting the update program to the nonvolatile memory, wherein the CPU executes the update application program stored in the volatile memory to output the update program to the nonvolatile memory, in response to the reset release signal.