At present, the PLC has been widely used in the industry area. But the disadvantage of this controller appears along with the development of the industry equipments. Such as worse compatibility cooperate with the new equipments, poor satisfaction of the high calculation and weak communication and so on. Thus, there need new technology to satisfy the increasing industry requirements. The soft PLC comes into the world from on kind of condition. The function of PLC is imitated through software on the PC platform. But the soft PLC has shortage also. The sturdiness and instantaneity is worse than the traditional PLC. Therefore, the embedded PLC combines the advantages of traditional PLC and soft PLC, increase the computing power, express the advantages of ladder diagram and open construction to bring a universal platform to the controlled members.