Patent ID: 8874989

Claim:
A device comprising: a transmission unit configured to be controlled by commands being received, and to transmit a response to each of the commands within a defined time, the commands each having a retransmission flag in an argument; and an error detection unit which detects a bit error, wherein the commands include a first command and a second command which is received after the first command, the retransmission flag of the first command is reset, the retransmission flag of the second command is set, and the second command has the same contents as the first command, if the second command is recognizable and the retransmission flag has been set, and when the first command is being executed, the device returns a normal response; and if the second command is recognizable, and the retransmission flag has been set, and when the first command is not being executed, the device returns a normal response if the second command can be executed, or returns an error response if the second command cannot be executed.