Compomease

This is the source code of my AI2618 Term Project, which aims to build a simple circuit to decide the type of components and to measure its parameters.

Academic Integrity

You can refer to the code in this repo, but with following limitations:

• If you refer to my code, by default you will abide by the license and the following rules：
• DO NOT directly copy and paste. Understand the code and write your own version.
• Indicate in your report that you referred the code here.

Basic Information

• MCU: Arduino nano ESP32 (with multiple channels of 12bit ADC, high sample rate, high)
• Framework: Arduino (easier to get started than ESP-IDF)
• Layout: breadboard (DO NOT CONNECT WITH THE PCB MODULE!)

MCU Program Framework

void initializePins();

• Launched: on startup
• Function: initialize pin configuration, initialize ADC resolution

void setHigh(low)Impedance();

• Launched: on demand
• Function: enable strong (weak) pullup and pulldown resistor

void generateCalibration();

• Launched: on startup
• Function: generate calibration data of the ADC using linear interpolation
• Input: previously measured voltage data
• Output: an array mapping binary data to voltage level, float[4096]

double repeatSample(uint8_t pin, size_t sampleTimes, unsigned long long delay_us);

• Launched: on demand
• Function: repeatly measure voltage level to reduce noise

void decideComponent();

• Launched: called by main()
• Function: decide the type of the measured component, send to host

void measureResistor();

• Launched: called by main()
• Functions:
  • Decide the resistor value range and switch measuring range
  • sample many times to reduce noise
  • send to host

void measureCapacitor();

• Launched: called by main()
• Functions:
  • Decide the capacitor value range and switch measuring range
  • Charge from 1/3u to 2/3u, and discharge from 2/3u to 1/3u to acquire capacitor value
  • send to host

void measureBJT();

• Launched: called by main()
• Functions:
  • Decide BJT type (PNP/NPN) using Ub
  • Modulate Ib with sigma-delta modulation
  • sample Uc with different Rc and Ib
  • send to host

Host Program Framework

• Language: Python
• Communication: serial
• Visualization: Matplotlib
• GUI Framework: tkinter, PyQt, etc.

Communication Protocol

#TODO

Involution Points

• Bluetooth Communication
• LCD display
• High-Precision Acquisition (with OPAMP, external ADCs, balanced bridges, etc.)
• PCB

References

ADC/Analog: https://docs.espressif.com/projects/arduino-esp32/en/latest/api/adc.html