Design Of Data Acquisition Device Based On Large Capacity Storage Card

Data acquisition can be used to collecte pressure signal, strain signal, vibration signal and so on. It plays an important role in debugging mechanical and hydraulic system, and it also help to dignose malfunction. Recently, technology about microelectronics, computer technology, measurement and control, digital communication is flourishing, so it requests the current collector must have much advantage, which is portable, low power consumption, convenient to use, and it have much sample rate and accuracy that can be selected. the data acquistion should have large storge capacity and abundantly computing processing function. Simultaneously, data acquisition based on microcontroller is limitted in dealing speed and computing ability. In order to resolve these problem, this article designes a protable device for data acquisition, which is based on the digital signal processor chip and the Secure Digital card.This paper devise a proposal about the data collector in hardware and software. Firstly, it determines the integrated function module: the data collector takes DSP as a core processor, which can compute data and control other chips in a high speed; The data collector store data into Secure Digital Card which has large-capacity storage space; Its power is provided by a portable lithium battery; Then it communivates with the host computer by Universal Serial Bus. Secondly, it devises hardware of the collector, this paper do all the work include that the chips selecting, the circuit designing, the PCB board designing, the components welding and debugging. Afterwards, It devises software of the collector. it compiles the code about intializing DSP chip, controling AD sample, storing data to SD card and founding the file system in the exploit environment of CCS2000. Finally, the data collector achieves the task of collecting, it does the operation of data acquisition, data processing and data storage in sixteen channel at the rate of 50K per second. Also it do the work of wave playing-back assistance in Matlab. The experiment proves that the device plays fine performance, which can meet the requirments.