An Applied Research On SCM System

The full name of SCM is Single Chip Microcomputer, also is called as Microcontroller Unit or Embedded Controller. This kind of microcomputer performs miniaturization to the basic components of a computer, and is integrated into a chip; in general a chip contains the following: CPU, ROM, RAM, parallel I/O, serial I/O, timer/counter, interrupt control, system clock and system bus, etc.From missile to navigation unit, including the various instruments in control in a plane, from Comm. & networking, and data transmission in computer to real-time control and data treatment in the process of industrial automation, including the various smart IC cards and electronic pet which have been widely used in our daily life, throughout the various fields in our current life they can't take away from SCM. For this reasons, it is highly necessary to deeply study in SCM. This thesis is started from the above thoughts, SCM is preliminarily discussed and researched in application against it's the following fields: automatic control concerning robot, and medical equipments concerning semi-automatic biochemical analyzer.Robotics are the modern technology faces to future, they belong to the high-new technologies just as network technology, gene engineering, communications technology and computer technology, etc. Definition of robot is diverse, in 1979 RIA defined robot as: a reprogrammable and multifunctional manipulator, and is designed to perform the various desks in mobile such as the raw material, the part, the tool or the special equipment by means of the various program actions. Our scientists define robot as: robot is a kind of automated machine, what is different now is that this kind of machine has some intelligent capabilities as or similar to human or living creature, such as perception, programming ability, motor ability and synergism ability, it is a kind of automated machine with high-level flexibility.With development of technology, The application of robots has been increasingly wide and deep, The robotics or the intelligence automation technologies has been taken top priority in strategy of science and technology development by all of developed nations and has been expanded, our country is a developing country, We must intensify research work, get hold of theory and technology, they should be discovered to the activities in production and research which are demanded as soon as possible.The robots have many mobile modes, mainly are divided into 2 kinds as the following: wheel-type and feet-type, the main technologies of wheel mobile mode are more mature and easy to control, the feet-type is difficult in walking way, however with development of sensor technology and microcontroller, and has come a long way. On the whole the system of Wheeled Mobile Robot (WMR) mainly contain: mechanical structure, DC servo motor, electric power source, detecting element, CCD camera, microcontroller, and module of Power Drivers. This thesis is started from the system structure of WMR, mainly design the hardware and software platform concerning to mobile control system of a robot. Firstly analyzing the mobile structure of un-complete wheeled mobile structure and the model of DC servo motor and setting up the control system module of a robot. Secondly, designing a mobile control system based on AVR microcontroller (AT90S8515), among them the following should be contained as the main: PWM power driving, measuring velocity unit and serial communication module, etc.; as for the velocity and position control of the robot, adopting the method of vague PID calculation can overcome the impact by indeterminacy of mobile robot module, diversity required by rate-of-tum position control and environment change. The procedure is programmed by ICCAVR C language, and emulated by ICE200 in AVR SUDIO debugging software.According to the difference of biochemical standard, Biochemical Analyzer is mainly applied for testing various biochemical standards in human body fluid in order to provide scientific reference for doctors confirming patient's condition. Its appearance greatly changes original situations such as frequent manipulate, great effects of manipulator's subjective factors and large error rate, caused by manual biochemical analysis. Biochemical Analyzer has many more types, it can be divided into four types according to structural style, including continuous type, centrifugal type, discrete type and dry chip type; it can be divided into two types according to the items tested by the instrument at the same time, including single channel and multiple channels: Biochemical Analyzer with single channel type can only test one item for one sampling, the multiple channels can test many items for one sampling at the same time; it can be divided into three types according to complexity of the instrument, including large type, meddle type and small type; and according to degree of automation, Biochemical Analyzer can be divided into full automatic and semiautomatic. At present, Biochemical Analyzer development level of our country is much lower, the development of full automatic Biochemical Analyzer is just beginning its step, and most instruments adopted by biochemical laboratory of small type hospital are semiautomatic Biochemical Analyzer at home. Thus develop research on semiautomatic Biochemical Analyzer has a certain significance and value for improving research level of Biochemical Analyzer. The purpose of this thesis is to introduce a new type of semiautomatic Biochemical Analyzer that has the characters of convenient manipulate, perfect function and Chinese user interface. This Biochemical Analyzer is used to In Vitro Diagnostic; it is mainly used to analysis of various biochemical standards in blood and other fluids in human body through photoelectric method to test the density of the fluid to be tested.Here we introduce operating principles and measuring method of semiautomatic Biochemical Analyzer firstly, according to performance index of Biochemical Analyzer to make overall design for the control system of Biochemical Analyzer and make clear and reasonable distribution of hardware and software function. Taking PIC16F774 single chip as the core has realized the hardware system of Biochemical Analyzer, completed the development and design of hardware platform, interface module, Small signal amplifying and logarithmic amplifying circuit module, and enabled the hardware platform to have a certain capacity of resisting disturbance. Utilizing photoelectric method to make signal test as well taking weak dark-current selenium photocell S1133 as photoelectric detecting element can improve test precision of Biochemical Analyzer.Using PIC assembly language to program the software procedure under PICMATE2004 integrated developing debugging environment, and completing the software design of Biochemical Analyzer control system. According to the requirement of systemic function, we divide the software into several modules with relative independent function, including serial communication module, display module, keyboard treatment module, A/D transformation module, and data treatment module, etc. The content of each module is mutual independent, which is convenient to program and adjust the procedure. During the test, Biochemical Analyzer requires that the sample need to be in normal temperature; the temperature control has great impact on performance analysis of the instrument. This design adopts method of vague control calculation, use integrated temperature sensor AD590 to test the temperature, and utilize PIC SCM to control Peltier temperature rise or temperature reduction. This method has the character of well control dynamic performance and strong stability. This design has complied with the localized developing trend of medical instruments; with the complete of development and promotion of the market, this instrument must bring prospective social benefit and economic benefit. In addition, the thesis discusses on stability of SCM in measurement and control domain.The system will be out of control when the CPU is impacted by the interfering signal. The most typical error is breaking the state value of PC, so that the procedure will fly in address field or involved in endless loop. While there are several methods to treat such situation as following: order redundancy technique; software snare technique; house dog technique.