#SecondLiChuangContest# Entries "Based on STM32/FPGA Virtual Oscilloscope/Signal Source/Frequency Sweep/Spectrum Analyzer"

1. Introduction to the work For example, it can include but is not limited to the following: 1. Pictures of the appearance of the complete machine or pictures of the welded and assembled PCBA; with an acrylic shell added for simple installation  

2. The research background, purpose, function, and market application prospects of the work; ** For electronic beginners, students, and many electronic enthusiasts, oscilloscopes are common tools, but they are quite expensive, with good ones costing tens of thousands, and ordinary ones costing as much. Thousands, which prohibits many electronics enthusiasts, especially students. Based on this, I came up with the idea of ​​making a digital virtual oscilloscope! The virtual oscilloscope has little hardware and mainly calculates and displays waveforms through the computer, saving most of the cost. ** 3. What are the highlights of the work in terms of innovation, interest, practicality and even public welfare? 1. The multi-function of the microcontroller is brought into play, and the USB can be plugged into the computer for use. 2. The mode is switched and the Bluetooth serial port is used to connect to the mobile phone. It can be used on the move, and the mobile phone display can be taken around. 3. It is sufficient for use within the parameter range. , after all, it is good to see some signals intuitively. It is not expensive. 2. System architecture diagram uses the form of flow chart or mind map to describe the structure of your work, that is, the scheme diagram. The figure below is the hardware block diagram of the virtual oscilloscope/signal generator. The main controller of the system is an STM32 microcontroller, and the FPGA is mainly used for high-speed data acquisition. The upper part of the figure is the virtual oscilloscope function. The signal to be measured is first processed by the amplification and attenuation circuit and the potential translation circuit, so that the signal is within the AD acquisition range. A FIFO is opened inside the FPGA to cache the data collected by the high-speed AD, and then sends the required data to the STM32 microcontroller according to the trigger conditions. The microcontroller then uploads the data to the computer through USB or sends it to the mobile phone through Bluetooth. Finally, the computer or mobile phone will The received data is drawn into a waveform and displayed to realize the oscilloscope function. The lower part of the figure shows the signal generator function. First, select the waveform to be generated on the computer or mobile phone, then send the waveform to the STM32 microcontroller, and then the microcontroller writes the data into the FPGA data ROM table. Finally, the FPGA sends the data in the data table to the DA at a certain frequency, and the DA generates an analog signal. The signal is then output through a low-pass filter and amplification/attenuation to generate the waveform we need. The host computer performs FFT transformation on the received waveform data, generates a waveform spectrum, and then draws the transformed image, so there is an additional spectrum analyzer function. The signal originates from the oscilloscope and is connected to the circuit at the same time. The host computer then controls the signal source to generate a frequency sweep signal with variable frequency. At the same time, the oscilloscope is used to measure the corresponding amplitude change of the circuit output and draw an amplitude-frequency curve, so there is an additional frequency sweep. instrument function.   3. Description of the hardware part 1. Attach a picture or source file of the schematic & PCB physical diagram (the official recommendation is that you try to upload the source file). If it is a picture, please make sure the picture is clear and legible;      the schematic picture is not very clear. , you can download the attached source file to view. oscsch.pdf  (Number of downloads: 1376)   AOK_OSC_SCH.rar  (Number of downloads: 1037) The schematic diagram was drawn by AD.    The PCB diagram is finally finished. . . . . AOK_OSC_PCB.rar  (number of downloads: 1073) You can download it and play. The PCB is drawn with PDS9.5.   2. Use words to briefly explain the implementation principle of the work and the working process of the system.          First, the input signal is processed through the amplification and attenuation circuit and the potential translation circuit, so that the signal is within the AD acquisition range. A FIFO is opened inside the FPGA to cache the data collected by the high-speed AD, and then sends the required data to the STM32 microcontroller according to the trigger conditions. The microcontroller then uploads the data to the computer through USB or sends it to the mobile phone through Bluetooth. Finally, the computer or mobile phone will The received data is drawn into a waveform and displayed to realize the oscilloscope function. 4. The material list (BOM list) lists the main components used in your work (key components are enough), such as microcontrollers & ARM chips, application-specific integrated chips (ASICs), sensors, functional modules, etc. If the chip listed is from our Lichuang Mall, it is best to write down the product number of the device or attach the corresponding purchase link.

Other components (resistance and capacitance) BOM download: AOK_OSC_BOM.rar  (Number of downloads: 694)  

5. Description of the software part (optional) If your work involves software, please list the software workflow diagram corresponding to the work, as well as the routines and source code of the key parts (please upload all the source code if you want to open source it). The host computer software is written in VB, and the oscilloscope is connected to the computer via USB. ** Oscilloscope interface: ** ** Signal source interface: ** Spectrum analyzer interface: ** Scan review interface: ** ** Android version APP The oscilloscope can be connected to a mobile phone via Bluetooth, and the signal can be measured with the mobile phone, making it easy to measure when out and about. ** The PC software is attached here for everyone to download and test. PC and APP.rar  (Number of downloads: 1256)   PC and APP latest version.rar  (Number of downloads: 872)   6. Work demonstration Please upload the function demonstration of your work to Tencent Video and edit it to this building (or attach it video link above). Uploading videos as required will earn you 5 points. Please see the event rules for details. Participation in the 2nd Lichuang Mall Electronic Production Festival "STM32-Based Virtual Oscilloscope"_Tencent Video   https://v.qq.com/x/page/o0538icr5g6.html The video uses a DuPont cable and a hand-held test function. It stands to reason that you need to use a probe. You can take a look.                               

7. Summary : For example, some of your experiences in completing the work, technical problems or debugging experience encountered, future plans for the work, and suggestions and opinions for our organizers, etc. 1. It mainly involves USB computers and microcontrollers, microcontrollers and FPGAs, as well as operational amplifiers in the front-end analog part. 2. There are some defective FPGA products. It is suspected that some pins are broken due to static electricity. 3. Generally speaking, it is a welding problem during debugging. That's basically it. Some computers have streamlined systems, so the driver installation cannot be successful. WIN10 default automatic driver is very powerful

For more project details, please see the link: http://club.szlcsc.com/article/details_6386_1.html

This project is owned by Lichuang Community " Xichengdao V3 "