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Hybrid electric vehicle has been quit popular,In the parallel arrangement hybrid electric bus, energy transfer process from engine to drive wheels has no energy conversion, compared with tandemvibratory Hybrid electric bus it is decorated with high transmission efficiency and lower fuel consumption, because parallel hybrid electric bus also need engine, because it has only two power systems ,so motor vehicle quality and cost and greatly reduced. Electronic mechanical transmission (AMT) accords to China’s national conditions, with the perfect function and reduce cost product development trend.Transmission electronic control units (TCU) is the core of AMT, hybrid electric bus AMT control depends on the software. various nesting feature, the logic structure of high complexity, there are different sampling information input and real-time and accurate output requirements control, hybrid electric bus AMT control belongs to the category of multitask real-time system. In order to realize the control strategy, the traditional software development methods TCU already cannot satisfy the growing complexity of AMT control, the real-time operating system is the inevitable trend, the real time and reliability design of real-time operating system can improve and develop AMT control software program, more convenient system changes and add expansion new functions. Based on uC/OS - II for kernel real-time operating system and MC9S12XDT256B as the controller chips based development board, combining the uC/OS - II real-time operating system and the AMT has its own characteristics, the system underlying driver for programming, mainly includes CAN communication, A/D transform, PWM motor drive, annual autocatalyst output speed several modules, try to determine each module partition as having different priority task: free time task, TCU initialization tasks, signal acquisition and input tasks, computing tasks, clutch location algorithm of computing tasks, task and shift shift control tasks, CAN send task, CAN communication communication received task and diagnosis task. Discuss the scheduling of intertask and analysis the clutch control displacement follow the control strategies method combining the real work, Select the control strategy and Validation effect with hardware in the loop testing
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