Research And Implementation Of System Programmable Testing Instrument

Nowadays,various kinds of testing equipments are widely used in scientific research and study.Due to the single function and large size of the instrument,the time and place of use of the test instrument is limited,and it can only be used in a fixed place such as a laboratory.This article studies system programmable testing equipment based on Cypress' s PSoC 5LP series CY8CKIT-050 development board which circuit is programmable.This paper designs a programmable testign equipment that integrates multiple measuring functions.The testing devices include digital multimeters,signal generators,digital oscilloscopes and so on.Based on this,the designer can make further expansion.The types of the design is as follows.1.The design of the hardware development board.A complete set of PSoC 5LP development board kits for this test instrument are designed,including a motherboard and a digital peripheral daughter board.The circuit functions include programming/debugger,PSoC 5LP basic system,extended power supply system,communication circuit,human-machine interface,multi-function configurable analog peripherals,etc.A four-layer board was used for the PCB design.The layout and routing ensured the performance of the analog circuit which including the function of fault tolerance design.2.Design a digital multimeter.This part realizes the measurement of resistance,voltage and current of DC and AC signals.The design which is based on the programmable PSoC development board uses programmable gain amplifie to amplify the multiples of the input signal.Adding a accurate Rectifier circuit to this circuit allows measurement of AC signal voltage and current which converts AC signals to DC signals before measuring.3.Design a signal generator.This part uses PSoC 5LP on-chip operational amplifier and external RC components to build sine wave,square wave and triangle wave generator.The implementation of arbitrary waveform oscilloscope is mainly realized by using a direct digital frequency synthesizer.The realization of Arbitrary Waveform Generator is implemented using both software and hardware instruments.4.Design of Digital oscilloscope.This section studied virtual oscilloscopes andstand-alone oscilloscopes.Signals are sampled in the development board,and the analog-digital converted data is transmitted to the PC through the USB communication interface.The microcomputer uses VC,CySuiteUSB development and application programs to perform waveform display of the virtual oscilloscope and other functions.The independent oscilloscope completes waveform acquisition and storage,trigger and time base,waveform processing,and display on the graphic LCD entirely in the development board.5.Realization of μC/OS-III Embedded Real-time Operating System on PSoC 5LP.This part provides the basis for the follow-up of this test instrument in terms of real-time,reliability,modularity,maintainability,and upgradeability.This article studies multi-function programmable test instruments.It have a high degree of programmabilitys hardware and software including circuit topology.Through programming switching,a variety of different instrument functions can be implemented on the same hardware platform.The instrument have low cost,small size and low power consumption.It is suitable for testing and measurement occasions where the frequency requirement is not too high.