CAN-bus Based Communication Application Layer Protocol for the Colliery Safety Monitoring System
一种适用于煤矿安全监控系统的CAN总线应用层通讯协议

In this paper,we proposed an application layer communication protocol which was suitable for CAN(Controller Area Networks) bus based colliery safety monitoring systems.After analyzing the frame structure of CAN 2.0B and the communication requirements of the monitoring system,we gave a definition for each bit of message identifier in the extended data frame to carry communication control information.Consequently,all of the eight bytes in the data field can be used to transmit actual data and then the CAN bus based communication efficiency was improved.The application layer protocol with multi-pipe technique can support the multi-thread communication between the transmitter and the receiver,and the command and captured data can be transmitted simultaneously in the monitoring system. The CAN bus short frame structure may result in the transmission failure of the large size data,while the frame number and bitmap technique can effectively solve the problem.Finally,the control protocol of the application layer and its frame format were briefly introduced.