An object is to provide a semiconductor device which includes an anti-collision function during or after production of an IC chip just by a change of a program, even when there is a change of a specification of a product accompanying a change of the kind or standard of a signal of a wireless means for each product. A semiconductor device includes an arithmetic circuit and a circuit for transmitting/receiving a signal to/from outside. The arithmetic circuit includes a central processing unit, a random access memory, a read only memory, and a controller. The read only memory stores a program for processing collision avoidance in transmitting/receiving the signal to/from outside. The program is executed in the central processing unit, so that the arithmetic circuit processes collision avoidance.