Study And Design Of The A.C. Sampling Remote Terminal Unit Based On μC/OS-Ⅱ

Embedded system is the most common application form from now on. It consists of hardware and software. Embedded system controls the action of the mechanism system by start-stop devices, gets input information by sensors and process the information by data processing parts.Taking example by the design of control system of the A.C. Sampling remote terminal unit (ACSRTU) device, general development process of embedded system is introduced in the paper The P80C552 MCU is the control center of ACSRTU. On the basis of giving attention to performance and cost, the hardware design which includes data collection circuits and device drive circuits and so on is introduced.Then the software of ACSRTU is completed, μC/OS-II is a kind of RTOS that has a preemptive kernel. The kernel of μC/OS-II is analyzed penetratingly and the software of the ACSRTU is completed on this basis. The multitasking of RTOS not oniy meets the real time requirement of the embedded system but also simplifies the design process and makes it easier to expand the system.Finally, some practical hardware and software reliability measures of embedded system are introduced in the paper. Such as, it discusses in particular measures to be taken for interference suppression in the input terminal and also those during the circuit board design.