Development Of Embedded Controller And Its Application In Process Experimental Unit

With the development of technology, the embedded system has been widely used in the field of industry control for the characteristics of high speed, large capacity and strong timeliness. As the embedded system has superior portability and the ability of internet communication and human-computer interaction, it is well expandable and can be conveniently embedded into other systems. Thus the embedded system may be possible to replace the control method based on micro-controllers and obtain great development. Therefore, in view of the structure system and function requirements of the process experiment equipment A3000, the subject studies and develops a kind of embedded controller suitable for industry process control based on C8051F023 and the embedded operating system Small RTOS51, and the subject also defines each function of the controller and designs the relevant monitoring and control software of the upper computer. The main work of the paper is the hardware circuit design of the embedded controller, the system software design and the control algorithm composition, the communication between the upper computer and the embedded controller, after practices , the monitoring and control to A3000 is realized based on the above finally. The following are the major work in this thesis:This paper confirms the general scheme of the control system and the principle of hardware design, develops main control module, power supply module, signal sampling module, analog output module, man-machine interaction module and communication module according to the functions of embedded controller, and the composition of each circuit module above is analyzed and discussed in detail.In this paper Small RTOS51 is adopted as software development platform after analysis and comparison of some kinds of RTOS, the processes of transplantation, configuration and clipping methods on C8051F023 are given in detail, and the superiority of RTOS is analyzed. This paper given task partition method reasonably based on system requirements。The system task is divided into TaskSample, TaskControl, TaskCom, TaskKey and TaskLcdDisplay respectively. Each task application program, driver program and the communication software of upper-computer are analysised and designed in detail. And this paper also develops relavant program codes to improve the system performance from software anti-interference measures. This paper realizes monitoring and control functions to the experimental unit by software of upper computer, including parameter display, dynamic curve drawing and sound and light alarm when parameters overrun. The embedded controller developed in this paper is applied to the process control experiment equipment A3000, and the control scheme is verified by the PID experiment.The application of this embedded controller on A3000 process control experimental device demonstrated the feasibility of the control scheme by the experiment of PID control.This paper ports embedded RTOS to small RAM processor, develops embedded controller, improves processor utilization efficiency by software methods, shorten software development period, and strenghens the stability, reliability and maintainability of control system. The development of the embedded controller has great reference value and significance to the improvement of control mode based on microcontroller.