Research On Scm-Based Data Acquisition Instrument For Locomotive Experiment Equipment

To meet the requirement of the project of Real-Time Monitoring andManagement Information System for Locomotive of Zhengzhou. It is necessaryto realize a distrbuted data acquisition and process system. This paPer aims atdeveloping a data acquisition insimment (DAI ) for locomotive testing equipmentbased on single-chip microcomputer (SCM). Data acquired from testingequipment can not only be printed on the spot, but also be transmitted throughRS-485 bus to control computeT, where data can be analyZed and processed.Based on the full use of internal resource of SCM, detailed measure methodsaccording to different parameters have been advanced to develop a suitable kindof DAl for locomotive testing equipment. This instrUInent has many advantages,such as high speed, accuracy, stability and powerful muItifunction as well asexcellent perfOrmance-price rate. With the successfuI debugging of anticipatedsotheare and hardware fUnctions, the instrument has been put to practical use.From this paper's work, not on1y deeper understanding of the idea of "testinteI;ration" have been achieved, but aIso new references have been offered as toSCM's applications in the test area of locomotive equipment.Chapter 2 first presents a general frame of the design ideas, and thendiscusses the requirement of system perfOrmance as well as the reasonab1eassignment of software and hardware. Finally, the necessary auxiliary means inthe deve1opment have been indicated.Chapter 3 introduces design methods of the data acquisition system mainlyincluding system software and hardware design. Hardware design, the main partof tlle system, stresses the signal regulating methods such as signal amplification,channel choice and am transfOrmation as we1l as the measure of usual parameterssuch as AC&DC electric parameters, contact resistance, time, temperature andpractical signal transfOrm circuit, etc. Furthermore, the anticipated functions havebeen proved by practical use.Chapter 4 studies the RS-485 communication been DAI and control PC.Interface design, communication protocol and communication software have alsobeen given in this part.Chapter 5 gives the extended circuit of DAI's peripheral interface. Thesoftware and hardware as to the functions of results dispIay and print is stressed.Chapter 6 proposes the anti-interference solutions in software and hardware in order toprevent the interference damage.