CAN be controller area network (Controller Area NetWork) for short. It is Germany developed by Bosch company and several other semiconductor manufacturers, was initially designed specifically for the automotive industry, the workload of aimed to save on wiring, because of its features were later widely used in all walks of life. Its chip production by Motorola, Intel and other companies. International CAN manufacturers and users of (the CIA) was established in 1993 in Europe, which is mainly to solve the practical problems in the application of CAN bus, provides CAN products and development tools, promote the application of CAN bus. At present CAN have technical Committee for approval as an international standard by ISO TC22, field bus, it was approved by the International Organization for Standardization is the only field bus.
CAN also follow the ISO/OSI reference model, the physical layer, data link layer and application layer. CAN use multi master works, regardless of their master/slave between the nodes, node between priority points, flexible communications, point to point, point to multipoint and radio transmission of data, no scheduling. Are nondestructive bus arbitration technology CAN, sent by priority, you can greatly save bus arbitration conflicts between, shows good performance under heavy load. CAN use short frame transmission, effective bytes per frame for 8, short transmission time, low probability of interference. Each frame has a CRC Checksum error detection measures, ensuring data error rate extremely low. When a serious error, with automatic closing function so that other nodes on the bus are not affected, so CAN be the most reliable of all buses. CAN bus twisted pair, coaxial cable or optical fiber can be used as the transport medium. Direct communication distance up to it 10km, communication speed up to 1M bps (range 40m), to hang the device on the bus to be mainly depends on the bus driver, up to a maximum of 110. But CAN be used in explosion-proof areas.