In some embodiments, a PLC system including a first CPU comprising a first media access control (MAC) communications layer and configured to generate data necessary for operation of the CPU, perform control operation based on the generated data, and transmit the generated data to a second CPU via the first MAC communications layer is included. The PLC system may further include the second CPU comprising a second MAC communications layer receiving the generated data via the first MAC communications layer and configured to perform service operation based on the received data. The first CPU may be connected to a memory in which data to be transmitted to the second CPU is stored at a predetermined location, and the second CPU may receive the data stored in the predetermined location of the memory by a direct memory access (DMA) scheme.