#The 7th Lichuang Electric Competition#USB Ammeter/Voltage Ammeter

Note: * is a required field,
please fill it in during the registration stage↓
 
* 1. Project Function Introduction
    The USB ammeter made based on N32G430C8L7+INA199 can check the current when the USB is working. There are 2 LED lights for debugging and working instructions, and 3 buttons for setting parameters. Because the LCD12864 screen is used, the display font is large, with charging capacity and charging time display, and it can also be used as a voltage and current meter alone. As an electronics enthusiast, I am very concerned about the capacity of the rechargeable battery and want to learn domestic single-chip microcomputer programming through this activity.
    Through parameter correction, the AD correction coefficient is saved in the FLASH of the N32G430C8L7 chip, which is convenient for calling the AD correction coefficient after power-on, thereby realizing the software correction of the voltage and current meter values. The main control chip
 
of the main device
    adopts the 32-bit N32G430C8L7 chip. One way is to sample the current through the R02 sampling resistor, and the sampling signal is amplified through INA199B1DCKR, and sent to the AD port of the single-chip microcomputer for quantization processing. The other way is to sample the current through the R02 sampling resistor, and the sampling signal is amplified through LM358, and sent to the AD port of the single-chip microcomputer for quantization processing. Compare the two signal amplifier circuits, and display them on the LCD12864 LCD screen.
 
Hardware design
1. Power supply circuit
2. Current sampling circuit
3. Voltage sampling circuit
4. Start selection
5. Reset circuit
6. MCU burning port
7. LCD12864 display
8. 2 LED lights
9. 3 buttons
10. Two USB outputs
11. Main control chip
12. Extension 1---external crystal oscillator
12. Extension 2---buzzer
13. BOM
 
 
schematic diagram
PCB
*2. Project attributes
The project is the first time to be made public, the project is original, whether the project has won awards in other competitions, and whether the project has participated in defense in school.
 
 
* 3. The open source agreement
 
supports open source.
 
Please fill in the form during the competition stage↓
 
*4. The hardware part
uses Jiali Chuang EDA.
 
Note: Jiali Chuang EDA is recommended. If you choose other EDA tools, please upload the schematic diagram in PDF format, the PCB drawing in PDF format, and the PCB file in Gerber format in the attachment. Here you can explain in detail the implementation principle and mechanism of your project, precautions, debugging methods, testing methods, etc. It is recommended to introduce your ideas to others in the form of pictures and texts.
 
*5. Software part
compilation software---Keil uVision5
    timer 6---10ms interrupt once, display---500ms refresh once, 4-way AD sampling, after recursive filtering algorithm, send to people for display. Function
 
realization
    The first time the power is on, through the confirmation key, first save the preset correction coefficient in FLASH, and then read the correction coefficient again. If the display is inaccurate, you can modify the correction coefficient through parameter correction to get the correct current and voltage values.
1. Normal display Voltage and current table USB1---current, capacity, time USB2---current, capacity, time USB----voltage External---voltage
2. Parameter correction USB1---current value fine-tuning correction USB2---current value fine-tuning correction USB----voltage value fine-tuning correction External---voltage value fine-tuning correction After the correction is completed, the correction coefficient is saved in FLASH. After the chip is powered on, the correction coefficient is read from FLASH first.
3. Backlight control Increase key-----turn off backlight Decrease key-----turn on backlight Confirm key-----turn on backlight
4. LED light LED1 light------temporarily unused LED2 light-----timer 0.5S flash
5. Ammeter USB1-------current, maximum range 3A USB2-------current, maximum range 3A
6. Voltmeter USB--------voltage, maximum range 3V External-------voltage, maximum range 30V
7. Capacity USB1-------capacity, maximum range 99.99ah USB2-------capacity, maximum range 99.99ah
8. Charging time USB1-------time, maximum range 9999 minutes USB2-------time, maximum range 9999 minutes
 

*6. BOM list
 
 
*7. Competition LOGO verification
 
* 8. Demonstrate your project and record it into a video to upload.
 
Video requirements: Please shoot horizontally, with a resolution of no less than 1280×720, in Mp4/Mov format, and a single video size limited to 100M;
Video title: Lichuang Electric Race: {Project Name}-{Video Module Name}; For example, Lichuang Electric Race: "Autonomous Driving"-Team Introduction.
 
More details: https://diy.szlcsc.com/posts/d76d9cb41705430e9a54e7a5feed07a5