Software Design Of 200 MSPS Sampling Rate' Virtual Oscilloscope

Traditional desktop oscilloscopes are generally large and not easy for users to carry around.Also they are not economically friendly to price-sensitive groups represented by personal research.Moreover,traditional digital oscilloscopes can't be adaptable to complex and changeable testing environment,such as the situation when the tester needs to keep a certain distance from the place where the tested signal inputs.Therefore,a new way of the development of digital oscilloscope has appeared.Owing to the features of miniaturized,modular and low-cost,virtual oscilloscope has attracted more and more attention.The 200 MSPS virtual oscilloscope in this paper removes the keyboard,display screen and other hardware devices.Meanwhile,it makes full use of the resources of Wi-Fi and USB,PC and mobile terminal.So the data acquisition system can be separated from the human-computer interaction terminal.And the functions of waveform processing and displaying are implemented on users' terminal devices.This paper first briefly introduces the domestic and foreign situation in the field of virtual oscilloscope,then introduces the hardware principle of the instrument,then analyses the software functional requirements of the instrument terminal and the terminal,and designs the overall scheme.It mainly introduces the design and implementation of the virtual oscilloscope in detail for the following parts:(1)Instrument driver of PC.This part includes the design of trigger channel,horizontal channel and vertical channel,the design of automatic setting algorithm of time base gear and vertical sensitivity,and the driver of arbitrary wave generator function at the instrument end.(2)The program of communication between host computer and ARM.The communication mode is USB interface and WiFi.The program includes the communication program of the upper computer and the communication program of the instrument.It includes the design of data package and instructions,the design of the sending,receiving and executing of instructions,and the non-blocking design of TCP communication.(3)The interface design of the host computer and the design of button control.Interface design includes the combination of multiple layouts,menu design uses a circular structure,button control is the design of control logic for special buttons,and the software design of waveform control in the stop state.(4)The communication program between ARM and FPGA.This part includes the design of parallel bus,data read-write and data reorganization.Finally,based on the existing hardware platform of the laboratory,the software is debugged and the main functions are tested.The results show that both USB interface and Wi-Fi mode can realize data communication function.The display of interface and menu conforms to the design.The automatic setting function of driver works well.The control function of special button works well.The data transmission between ARM and FPGA and the function of arbitrary waveform generator also works well.