Design And Implementation Of Display And Control Software For Frequency Counter

Frequency counter is the basic and important instrument in the field of electronic measurement.With the development of information technology,the measurement functions of frequency counter become more and more complex.Besides the frequency measurement,frequency counter is also capable of measuring time,pulse,phase,and other specifications of the input signal.In order to meet the measurement demands mentioned above,and also to support new measurement functions in the future,this thesis designed a display and control software for frequency counter based on the Vala language and GTK graphics library,which can measure a variety of parameters and support the extend of measurement function.The main contents of this thesis are as below:(1)Implementation of display and control function of the frequency counter.The software is divided into display module,driver module,data processing module and data container module.Each module is implemented with the idea of hierarchical design and MVP design pattern.Method calls and data transmission between layers and modules are implemented by signals,which can increases flexibility and reduces coupling.Measurement modes and data processing methods are abstracted with the idea of interface-oriented programming,which realized the unified control of measurement modes and the arbitrary combination of data processing methods,providing a feasible solution for the extension of new functions in the future.Containers storing configuration and measurement data are designed,with the features of persistent storage,centralized management and changes notification.(2)Analysis of the errors in each data processing procedure.For the random errors in the raw measurement data generated by the hardware,an error distribution model is built and applied in the correction.For the random bit errors in the route of data transmission through the interface,gross error detection is performed using the judging criterion.For the errors generated during the representation and calculation of floating point numbers,analysis results show that the accuracy requirements are still met in the worst case.With testing and verification,the frequency counter display and control software designed in this thesis has the ability to adjust the measurement parameters in real time,control the measurement hardware for multi-channel measurement,and combine multiple measurement procedures.The software can also calibrate the systematic errors and correct the random errors.The final results of the measurement items are displayed in the form of numerical value,histogram or trend plot.