A programmable logic controller includes a CPU unit. The CPU unit has a real IP address and a pseudo IP address different from the real IP address, transmits and receives data by using the real IP address to and from a communication device belonging to a network in which communication is performed using a first communication protocol, and transmits and receives data by using the pseudo IP address to and from a communication device belonging to a network in which communication is performed using a second communication protocol different from the first communication protocol.