Timing analysis of worst case with direct NM of OSEK NM

Abstract

This paper presents the worst case network situation and the analyzed result for timing test on real embedded system. Timing is critical fact in a specific network. As the needs that vehicle is more intelligence, electrical components of vehicle are more enhanced and complicated. The number of electronic control units (ECUs) which are set up at vehicle is significantly increased. Therefore there is the huge network compounded with a lot of ECUs in automotive system. The more nodes connected and having variable functions, the network has higher probability to occur fault. The fault of network may cause extremely dangerous accident, especially automotive network. There is strong trend that ECU use Open Systems and their Interfaces for the Electronics in Motor Vehicles (OSEK) which is real time OS for automotive system. OSEK has network management tool which is OSEK network management (OSEK NM). Direct NM, which is one of management rule of OSEK NM for a network of ECUs that communicate via a CAN bus is chosen for this paper. The variable time is important factor in real time system. The repairing mechanism of direct NM is analyzed. The main contribution of this paper is to investigate the worst case for the timing of network management with the management mechanism of OSEK NM. For that purpose we tested each case on real embedded system with changing various circumstance variables and the analysis on the time result of the test is proposed.