Starvation free controller area network using master node

Controller Area Network (CAN), a serial communication protocol, is widely used in industry in embedded applications. The fixed priority arbitration mechanism in CAN results starvation of lower priority nodes because in the presence of a set of higher priority messages, the low priority nodes are restricted to appear on a CAN network. Since lower priority messages can not change their priorities so they suffer from starvation and continuously lose arbitration due to the presence of higher priority messages. This paper addresses this problem and proposes a method to make a CAN network starvation free by adding a Master node in a CAN network. This Master node is fully capable of changing priority of starving node and allows the starving nodes to appear on a CAN network. It makes the CAN network starvation free and provides the ability to change priority dynamically. Master node monitors CAN network and remains silent until it keeps receiving messages of all the nodes and become active on detection of starving node, a node not contributing in communication. In active mode, this node tries to make sure that each node keeps participating in communication. A hardware setup along with CAN king Software has been used to verify the results.