The Design And Application Of One Small Real Time Operating System

This dissertation mainly introduces a method that design a Real-Time operation system based on MC9S08GB60. The smallest system of MC9S08GB60 is used as hardware platform, MC9S08GB60 is one of HCS08 series microprocessors produced by Freescale(a subsidiary of Motorola) Company. With the rapid progress of semiconductors producing technology and the higher level of chip designing, the performance of the MCU (Microcontroller Unit) has been improved greatly, and the application of it has been scaled greatly. It is difficult for the previous former-background software design method to adapt these changes. So we adopt Embedded Real-Time Operation System software design method that replaces traditional former-background (super loop) method, in order to combine its powerful function with the more demands that people bring forward for IT products.RTOS is a new system design conception and an open software frame. It has operation system function that can control the whole Real-Time system and in order of importance and urgency of every task, it rationally assigns CPU and different resources holding time between them. It improves the service efficiency of CPU using semaphore, mailbox and so on Functions. The multitasking of RTOS not only meets the real time requirement of the embedded system but also simplifies the design process and makes it easier to expand the system.This thesis is composed of five parts. In the first place, we briefly introduce the basic concepts of the Embedded RTOS; then, describe the smallest system of MC9S08GB60 MCU, which includes PCB board, monitor program and in-circuit programming system; thirdly, explain the design of core structure, task management,time management, task communication and synchronization and so on in detail, supply the test program and analyse the source which engrossed by the kernel; fourly, discuss the design method of the hardware and software on application system, it is a right example for the calorimeter of central heating; at last, handle this subject concisely and discusse some unsolved aspects of our studies and probe into the prospect of SDF-RTOS.