Embedded Real-time Operating Systems, Application Development Uc/os- ¢ò Study

Embedded system is widely used in many fields today. At the same time, Embedded Real_Time Operating System (RTOS) plays the most important role in Embedded System and it has become an important branch of operating system. The purpose of this paper is to study how to use the RTOS. Firstly, we build a hardware platform based on 186 CPU. The hardware platform includes 512K bytes FLASH RAM (used to stored data and program), 3 UART COM (used for GPRS communication or RS232 or RS485), integrated LCD displaying, simple keyboard including 16 keys, 10 bits data general input and output ports, abridge ISA bus(to extend other devices) and watch_dog etc. secondly, we finished the hardware drive programming and called them HAL(Hardware Abstraction Layer). The HAL was used by upper layer user or system. At last, we ported the uC/OS â…¡ kernel to the hardware platform and studied the user programming on the embedded system, including system principle and porting details.In this paper, the source code of uC/OS-â…¡ was analysed first. By this we knew the theory of kernel: task management , time management , the communication and synchronization of tasks and memory management etc. There are many data we can use in this field , but you can hardly understand the RTOS only by analyzing uC/OS â…¡ (reference 1). You should understand the theoery of Operating System to the core , then study some typical Operating Systems (reference 4,10,12,13,17,18 etc.). At last , you can study uC/OS â…¡ in detail, analyse the code under guidance of theory.In this paper , many questions were discussed including how to build the hardware platform , how to build the HAL .Then a practical item was finished based on traditional back_and_fore platform programming (used to analyse the content of chemical matter and display the received data in real time).Then we studied the process of porting uC/OS â…¡ to the hardware platform . Because uC/OS â…¡ is a kernel where only the base function of managementwas provided , so it has to be expanded to an integrity embedded real_time multi_task operating system . A typical character of our system is that the HAL includes the DOS kernel and device driving, because we used the DOS kernel as the hardware boot_loader. At last, the normal user task programming was discussed in this paper . ( Restricted by my ability and time , the actual task deviding and the design of task_communication were not included in my job.)...