Documentation for Python Code to Plot Arduino Data in Real-Time

Overview

This Python code uses the serial library to read data from an Arduino microcontroller, and the matplotlib library to plot the data in real-time. The code continuously reads data from the Arduino and adds it to a list of values that is plotted using matplotlib.

Dependencies

This code depends on two Python libraries:

1. serial - This library provides a way to read data from a serial port. You can install it using the command pip install pyserial.
2. matplotlib - This library is used for plotting the data. You can install it using the command pip install matplotlib.

Usage

1. Connect your Arduino to your computer and make note of the port that it is connected to. In this code, the port is assumed to be COM4. You may need to change this depending on your setup.

2. Upload the following code to your Arduino:

void setup() {
  Serial.begin(9600);
}

void loop() {
  float value = analogRead(A0) / 1023.0 * 5.0;
  Serial.println(value);
  delay(10);
}

This code reads the value from analog pin 0, converts it to a voltage between 0 and 5 volts, and sends it to the computer over the serial port. 3. Run the Python code in your preferred Python environment. You should see a live plot of the data from the Arduino.

Code Explanation

1. Import the necessary libraries:

from serial import Serial
import matplotlib.pyplot as plt

2. Create a Serial object to read data from the Arduino:

ser = Serial('COM4', 9600)

This assumes that the Arduino is connected to the computer via the COM4 port and is sending data at a baud rate of 9600.

3. Set up the matplotlib plot:

plt.ion()
fig, ax = plt.subplots()
ax.set_title('Light Sensor')
ax.set_xlabel('Time')
ax.set_ylabel('Light Intensity')

This sets up an interactive plot, creates a new plot figure, sets the plot title, and labels the x and y axes.

4. Create empty lists to store the data:

x, y = [], []

5. Create a Line2D object to plot the data:

line, = ax.plot(x, y)

6. Continuously read data from the serial port and plot it:

while True:
    try:
        data = ser.readline().decode().strip()
        x.append(len(x))
        ligma=1000-float(data)
        y.append(ligma)

        line.set_data(x, y)

        ax.relim()
        ax.autoscale_view(True,True,True)

        fig.canvas.draw()
        fig.canvas.flush_events()
        
    except KeyboardInterrupt:
        ser.close()
        break

This loop reads data from the serial port, converts it to a float, and appends it to the x and y lists. It then updates the plot data with the new x and y values, and redraws the plot.

7. When the loop is interrupted by a keyboard interrupt, the serial port is closed:

ser.close()

This ensures that the serial port is properly closed before the program exits.