Power Line Carrier-based Embedded Protocol Converter Design

There are several kinds of communication methods in electrical communication, including fiber communication, the power line carrier communication and microwave communication, when different methods of communication exist at the same time, the protocols which suit for different equipment should be converted.In this paper, a protocol converter of power line carrier communication is designed, this converter can fulfill the convert among 101 protocol, CDT protocol and Modbus protocol. According to power line carrier net uses the way of principle and subordinate, a converter is needed at both the host and the guest, the acquisition, processing, uploading of RTU data are finished at the guest, and the polling, data uploading and order transferring of the transferring center are finished by the host. The design consists of two parts, the first part is the hardware design, the PHILLIPS LPC2387 is used to be the main controller, the peripheral circuit modules, including watch dog module, photoelectricity seclusion module and RS232 voltage level convert module are designed. At the end of this part, the system chart and PCB are designed. The second part is software design, the process of power line carrier protocol convert is discussed in detail, the polling system between host and guest is researched, the coding is mainly done on the guest of protocol converter,include RTU data process and host request response.