Ammeter and Voltmeter Training Camp

This project uses a LCSC Wenxing (Wuhan Xin Semiconductor Source CW32F030C8T6) development board to create a voltage and current meter. Voltage is displayed in V units, with a measurement range below 34V (1.5V * 2^3 = 34.5V). The ADC internal reference is 1.5V, and the sampling resistor voltage division ratio is 1/2^3. The range can be increased or decreased by changing the voltage division ratio. Current is displayed in A units, with a measurement range below 5A, because the current sampling resistor is 0.1R/3W. The code functionality was modified based on the official solution. Button SW1 is for on/off display, SW2 is for measurement reference (2.5V provided by TL431 – this requires changing the ADC internal reference to VCC or an external reference of 3.3V to avoid exceeding the range), and SW3 is for actual voltage and current measurement. J1 is for an external OLED display, which is optional. Voltage measurement has two ranges: high and low, automatically switched by the program with a switching threshold of 1.5V. Indicator L1 illuminates during the high voltage measurement range and turns off during the low voltage measurement range.