This paper addresses the Data Distribution Service DDS publish/subscribe middleware, which uses CAN driver and its State manager under μCOSII real-time operating system. Our research work consists on developing a real-time middleware in the C language. Starting with the Object Management Group (OMG) specification, which is developed in interface description language (idl) file, we use the idl to C mapping rules to create the Data Centric Publish Subscribe Application Programming Interface (API). We attach a special attention to DDS listeners and we give an approach to establish low-level communication using listeners, callback functions and CAN state manager. We specially focus on the default response of DDS entities following the ISR (Interrupt Service Routine) as communication behavior.