Serial Plotter¶

The Arduino Serial Plotter is a tool that allows you to visualize data from your Arduino board in real-time. It can be used to plot sensor data, waveforms, or any other data that changes over time.

Example: Plotting a Sine Wave with the Arduino Serial Plotter¶

A very simple way to try out the Arduino Serial Plotter is to create a sketch that sends some varying data to the serial port. The Serial Plotter can graph this data in real-time. One of the simplest examples is to plot a sine wave. Here’s a basic sketch to do this:

// Include the math library to use the sin() function
#include <math.h>

// Declare a variable to keep track of the angle
float angle = 0.0;

void setup() {
  // Initialize the serial communication at a baud rate of 9600
  Serial.begin(9600);
}

void loop() {
  // Calculate the sine of the angle
  float value = sin(angle);

  // Print the value to the serial monitor
  Serial.println(value);

  // Increment the angle
  angle += 0.1;

  // Reset the angle if it exceeds 2*PI
  if (angle > TWO_PI) {
    angle = 0;
  }

  // Wait for 100 milliseconds before the next loop
  delay(100);
}

Explanation:¶

1. Include Math Library:

2. #include <math.h> includes the math library to use the sin() function.

3. Variable Declaration:

4. float angle = 0.0; declares a floating-point variable named angle and initializes it to 0.0.

5. Setup Function:

6. Serial.begin(9600); initializes serial communication at a baud rate of 9600 bits per second.

7. Loop Function:

8. float value = sin(angle); calculates the sine of the current angle.
9. Serial.println(value); prints the sine value to the serial monitor.
10. angle += 0.1; increments the angle by 0.1 radians.
11. if (angle > TWO_PI) { angle = 0; } resets the angle if it exceeds 2π (a full cycle).
12. delay(100); waits for 100 milliseconds before the next iteration of the loop.

Using the Serial Plotter:¶

1. Upload the sketch to your Arduino board.
2. Open the Serial Plotter by navigating to Tools > Serial Plotter in the Arduino IDE.
3. Ensure the baud rate is set to 9600 in the Serial Plotter.
4. You should see a sine wave being plotted in real-time.

This sketch provides a simple way to visualize data using the Serial Plotter. You can modify the angle increment and delay to see how it affects the plotted sine wave.

Additional Tasks¶

1. Modify the Angle Increment¶

Write a program that modifies the angle increment to change the frequency of the sine wave plotted on the Serial Plotter.

#include <math.h>

float angle = 0.0;

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

void loop() {
  float value = sin(angle);
  Serial.println(value);

  // Change the increment value to modify the frequency
  angle += 0.05; // Smaller increment for a higher frequency wave

  if (angle > TWO_PI) {
    angle = 0;
  }

  delay(100);
}

2. Use a Different Mathematical Function¶

Write a program that plots a different mathematical function, such as a cosine wave, on the Serial Plotter.

#include <math.h>

float angle = 0.0;

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

void loop() {
  // Use the cosine function instead of the sine function
  float value = cos(angle);
  Serial.println(value);

  angle += 0.1;

  if (angle > TWO_PI) {
    angle = 0;
  }

  delay(100);
}

3. Plot Multiple Waves Simultaneously¶

Write a program that plots both sine and cosine waves simultaneously on the Serial Plotter.

#include <math.h>

float angle = 0.0;

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

void loop() {
  float sineValue = sin(angle);
  float cosineValue = cos(angle);

  // Print both values separated by a comma
  Serial.print(sineValue);
  Serial.print(", ");
  Serial.println(cosineValue);

  angle += 0.1;

  if (angle > TWO_PI) {
    angle = 0;
  }

  delay(100);
}

These tasks will help you explore more features of the Arduino Serial Plotter and understand how to manipulate and visualize data in real-time.