CAN_bus is Used in Access Control System
As an integral part of public safety, the reliability, safety and stability of the access control system is a very important indicator. And CAN_bus has the characteristics of multi-master structure, reliable error handling mechanism, and the node automatically exits the bus in the case of serious errors, so that CAN_bus has a strong advantage in the access control system.
CAN-bus (ControllerAreaNetwork) is the controller area network, which is one of the most widely used field buses. At first, CAN-bus was designed as a microcontroller communication in the automotive environment, exchanging information between ECUs of various electronic control devices in the vehicle to form an automotive electronic control network. For example, the CAN control device is embedded in the engine management system, transmission controller, instrumentation equipment, and electronic backbone system. Because of its advanced technology, high reliability, perfect function and reasonable cost, CAN_busCAN-bus has been widely used in various automation control systems. For example, in automotive electronics, automatic control, intelligent buildings, power systems, security monitoring and other fields.
CAN-bus is a multi-master serial communication bus with high bit rate, high immunity to electromagnetic interference, and the ability to detect any errors that occur. When the signal transmission distance reaches 10Km, CAN-bus can still provide a data transmission rate of up to 5Kbps.
In the CAN_bus access control system, the twisted pair is used as the transmission medium, and the network connection adopts the bus connection method.
In the traditional RS485 bus, when an error occurs in a node, it will affect the operation of the entire system, and even cause the paralysis of the entire system, high maintenance costs, and complicated network debugging. The CAN controller automatically performs error handling when an error occurs in the node, and automatically exits the bus function when the error is serious, which will not affect the operation of the entire network, greatly improving the security of the system, and reducing the workload of network debugging and maintenance. Cost becomes lower.
