Study And Implementation Based On BACnet

With the development of information technology and the increasingly high demand in intelligent, energy conservation, comfort and safety of the building, the application of Intelligent Building is more and more widely. Intelligent Building is generated by combining traditional building with computer technology, network communication technology, automatic control technology, multimedia technology and sensor technology. Because of the history of the development of building technology and competition from various manufacturers, different manufacturers produce the building intelligent devices with the different standards. It results in Incompatibility of different systems, so it cannot achieve integration of Intelligent Building. In order to make products from different manufacturers to achieve interconnection, interchange and interoperability, and connect with the entire Internet, Standard Project Committee: SPC135P,which was established by ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.) in1987. developed a standard for building automation and control. This standard is A Date Communication Protocol for Building Automation and Control Networks (BACnet). It was released in1995. and became the ISO standard of Construction industry in2003.After a deep discussion of BACnet, the BACnet protocol stack is designed. According to the four layers of the protocol stack, the BACnet is divided into three main modules:application, network and data link. Sub modules, such as the service module of BACnet, the object module of BACnet, interface module, state machine module, and coding/decoding module, are designed and implemented in the module of application layer. The function of the module of network layer is to send, receive and process the message of network. The technology, include MS/TP and BACnet/IP, is used in data link layer, and it can communicate with the Internet.At last, the stack of implementation is transplanted into STM32. It is function test test with the VTS of testing software. And the stack can work as expected.