| This paper studies on design and application of embedded operating system based on two typical microcontroller (S3C44B0X and STC89C516). The microcontroller S3C44B0X is used in the master controller which consists of human computer interface, communication port and JTAG. The programme in the master controller is organized with a operating system transplanted from M icroC/OS- II. Microcontroller STC89C516 is employed for slave controllers which are distributed and mainly focus on real time control. A time-triggered operating scheme is developed for of the slave controllers to obtain reliability and robustness. For system controlling a multi-control technique is adopted based on CAN bus communication.At last the paper specifies that distributed control system is applied on a project of charge and discharge for battery storage. Application software of master controller consists of two parts. The first one is to deal with the input, edit and save of control parameters. The other has the functions of transmiting parameters, controlling commands and receiving data. Priority of task accords with sequence number of slave controller. All tasks can communicate each other by message mailbox. Display task respond interrupt call of keyboard by message mailbox. When all task have been suspended, a leisure task will have been executed. Application software of a slave controller consists of five tasks. Receiving and transmiting messages of CAN bus is a preemptive task, which receives processing parameters and controlling commands and transmits data selectd by slave controller. The task of AD conversion gets the value of current and voltage, so as to compare with the reference value set in processing parameters. The task of PID arithmetic for close-loop adjustment ensures the controlling precision of charge and discharge. The task of display is used to display the current, voltage and time of process which is calculated by the tick of timer.
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