The Research On High Speed Data Acquisiton System Based On DSP

Highly developed in today's society,The great and rapid development of technology and Highly automated production process has become known as an inevitable trend, and their commom requirement is to have buit on the continuous development and enhancement of the basis of the information industry. It is only from the outside world access to a large number of accurate and reliable information, and a series of scientific analysis, handling, processing and determine to achieve a high degree of automation. With the great development of IC technology and rapid development of computer technology in recent decades,these provide a very good and reliable scientific and technological base for data acquisition and processing, at the same time,a higher demand on data acquisition and processing is required. Traditional data acquisition system are generally single-chip microcomputer as the core , combined with the external data processing circuit, A/D conversion circuit and control circuit to complete the collection of data. But the single chip because of its limited resources, computing and data processing capability is insufficient to meet the high-precision data acquisition and processing requirements. Digital signal processor is a specialized for real-time, rapid achievement of a variety of digital signal processing algorithms designed which using the Harvard architecture microprocessor. DSP chip processing equipment is dedicated to the digital form of signal acquisition, transformation, filtering, valuation, increased compression, recognition processing, in order to get the needs of the people of the signal form. It has convenient interface, good stability, high accuracy and repeatability. With the rapid development of DSP chips, which have powerful function, the rising cost-effective and time of design is shorten. Therefore,this paper discussed a DSP-based high-speed data acquisition system. The mainstream of the current processing speed of DSP chips is very fast,in fact,these DSP run at speeds of up to 10,000 per second,tens of complex instruction program.this is far exceeding the general mircroprocessor. Further,the DSP,As a dedicated digital signal processing chips, is particularly suited to digital signal processing algorithms for the computation.this have a great advantage for the following digital signal processing. Therefore the use of DSP as the core for data acquisition system, can be very good to meet the real-time systems, high-precision and versatility. In this paper,the main work is to design DSP_based data acquisition system of hardware circuit and its corresponding software design. The main thesis of the chapter two is focused on the hardware of system design: 1.DSP minimum system design, including the clock circuit, power circuit,reset circuit,JTAG circuit, mainly in order to achieve simulation,debugging and other online features,the circuit of memory expansion is necessary for a large mout of data processing system. The DSP minimum system to ensure the normal operation of DSP chips.2. Signal pre-processing module,the main work of this module is make the analog signal to scope of required input of analog-to-digital conversation part by filtering, enlarge,bias processing.the anti-aliasing filter circuit is 8-order Butterworth low-pass filter.3.Digital-to-analog convert module, this module is the most important part of data auquisition system.its performance will directly affect the performance of the system. In this paper,our starting point is that high-speed data acquisition system,and take into account considerations such as accuracy,we chose AD9244 as the system A/D converter chip.4.Man-machine interface circuit. In order to make the whole system have a good man-machine interface,we add a piece of 128×64 dot-matrix graphic LED in the system to give the visual data that have collected and processing to user.5.Communication circuit .Make use of the HPI interface of the DSP chip to complete the communication between master and slave microprocessor.6.CPLD module.since the DSP chip we choose for system do not have enough I/O port,so we take advantage of the CPLD module to expand the external I/O port,and also wo use the CPLD module to generate the logic control signal for system. This will greatly reduce the load of DSP chip,and DSP chip will have more capacity to carry out digital signal processing algoritum and greatly improve the overall efficiency of the system. Chapter three of the paper focused on the system software design. First of all,we dicuss the directive system and DSP software development process.Then,we give a detailed discussion about how to write DSP command file and the interrupt handing routine based on C language,for each part,we give a segment program.Finally,we discuss the software design of LED.Chapter four of the paper discusses the notes of the system design: 1.Because of the frequency of the system is high,we introduce the optimization measure and anti-jamming measure in the PCB manufacturing process.2.This system have many peripheral ciucuit,therefore there is a problem about voltage conversion between various types of chips.We summarize the various types of level-shifting,and we also give the solution for the corresponding level-translation. In this paper,we put forward a realizable design of a high-speed data acquisition system.system uses a modular design,easy installation and maintenance, combinate the design mind of the embedded system,make use of the srongpoint of DSP,the system have achieved small size,low cost,real-time,high accuracy. All of these,make this system have a good application prospect.However,there are some improvements places in the system. We can add a FLASH memory into the the DSP minimum system,then we use the BOOTLAOD of DSP to achieve the quick start.this will improve the efficiency of the system furthermore.