Heart Beat Display using Pulse Sensor with Arduino & OLED

The Heart Beat Display using Pulse Sensor with Arduino & OLED is a project that displays the user’s heart rate on an OLED display using an Arduino and a pulse sensor. this project is perfect for anyone interested in health monitoring, or wearable technology. Start making your Arduino heart rate monitor today.

The project is controlled by a simple code that reads the heart rate sensor data and displays it on the OLED display. Pulse sensors can be used to track the user’s heart rate and can be used to monitor their health in real time.

A pulse sensor is used to measure heart rate by detecting the amount of blood flow through the body.
Arduino is used to process the signal from the sensor and calculate the heart rate.
OLED is used to display the heart rate in beats per minute. The system can be used to monitor heart rate in real-time or to record heart rate data over time.
Required Material

Required Material

You will need the following components

Arduino Board
Pulse sensor
0.96″ OLED display
Jumper wires
Breadboard

Pulse sensor Arduino

A pulse sensor can measure the changes in blood flow generated by your heartbeat. Pulse sensors can be placed on different parts of your body, such as your fingertip, or wrist. Pulse sensors are generally used in health and fitness tracking, as well as in medical settings to monitor patients’ heart rates.

The pulse sensor uses a light source and detector to detect the changes in blood flow. Your heart pumps blood through your body, and the amount of blood in your blood vessels changes with each beat. It works by shining a light glow into your skin and calculating how much of that light is absorbed by your blood vessels.

Pulse sensor Pinout

The pulse sensor has three pins: VCC, GND, and analog Pin.

Pulse sensor Schematic

Pulse sensor Specs

Powering:

Operating voltage: 3.3V to 5V DC
Current consumption: less than 10mA

Heart rate measurement:

Detection Method: Photoplethysmography (PPG)
Detection range: 30 to 200 beats per minute (BPM)
Accuracy: +/- 1 BPM
Resolution: 1 BPM
LED Wavelength: 660nm or 940nm (depending on the model)

Physical dimensions:

Sensor size: 20mm x 10mm x 5mm
Weight: 3g to 5g

Environmental conditions:

Operating temperature: -10°C to +50°C
Operating humidity: 0% to 90% non-condensing

Applications of pulse sensors

Health and fitness tracking
Sleep Tracking
Medical monitoring (e.g. in hospitals, ambulances)
Consumer electronics (e.g. smartwatches, fitness trackers)
Remote patient monitoring
Smart Health bands

Warning: This sensor has not been approved by the FDA or any medical. It is created for use in hobby projects and demonstrations only.

0.96″ I2C OLED Display

A 0.96″ OLED display is a small, low-power display that uses the I2C protocol to communicate with a microcontroller board. the I2C interface requires only two data lines (SDA and SCL) to transfer data.

OLED (Organic Light Emitting Diode) technology allows the display to emit light without a backlight, resulting in deeper blacks and higher contrast ratios than traditional LCD displays.

OLED display measures 0.96 inches diagonal and is normally used in small electronic projects due to its compact size and low power consumption.

0.96″ I2C OLED Display Pinout

The pinout for the 0.96″ I2C OLED Display is as follows:

GND: Ground connection
VCC: Power supply (usually 3.3V or 5V)
SCL: I2C clock signal input
SDA: I2C data signal input

Schematic diagram – Heartbeat sensor Arduino

To connect the pulse sensor with the Arduino, first, connect the VCC pin of the sensor to the 5V pin on the Arduino and connect the GND pin of the sensor to the GND pin. Next, connect the signal pin of the sensor to Analog pin A0.

Pulse Sensor	Arduino Uno
Positive	VCC pin (5V)
Negative	GND pin
Signal	A0 pin

For the OLED display, you first need to connect the VCC pin of the display to the 3.3V pin and then connect the GND pin of the display to the GND. connect the SDA and SCK pins of the display to the A4 and A5 pins respectively.

OLED Display	Arduino Board
VCC	5V
GND	GND
SDA	A4
SCL	A5

Code & Libraries – Pulse Sensor With Arduino & OLED

Download and install Adafruit_GFX and Adafruit_SSD1306 libraries for Arduino.

1 2	#include <Adafruit_GFX.h> #include <Adafruit_SSD1306.h>

Example Code Arduino Pulse Sensor

You can use the Arduino IDE with a unique feature that is using an in-built serial monitor plotter to display your heartbeat graphically on the serial monitor window. You will have to load the code below into your IDE and upload it to Arduino. Then select “Tools->Serial Plotter”

void setup() {

Serial.begin(9600);

}

void loop()

{

Serial.println(analogRead(0));

delay(20);

}

Here’s my screenshot showing you what to expect.

Source Code

Open Arduino IDE and create a new sketch Copy and paste the following code:

// Include Libraries
#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

// OLED screen size in pixels
#define SCREEN_WIDTH 128  // OLED display width, in pixels
#define SCREEN_HEIGHT 64  // OLED display height, in pixels

// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
#define OLED_RESET -1 // Reset pin # (or -1 if sharing Arduino reset pin)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// Variable Declarations
unsigned long previousMillisGetHR = 0;     // Store last time Millis (to get Heartbeat) was updated.
unsigned long previousMillisResultHR = 0; // Store last time Millis (to get BPM) was updated.

const long intervalGetHR = 20;     // Interval for reading heart rate (Heartbeat) = 10ms.
const long intervalResultHR = 10000; // The reading interval for the result of the Heart Rate calculation is in 10 seconds.

int PulseSensorSignal;      // Variable to accommodate the signal value from the sensor
const int PulseSensorHRWire = 0;  // PulseSensor connected to ANALOG PIN 0 (A0 / ADC 0).
const int LED_A1 = A1;            // LED to detect when the heart is beating. The LED is connected to PIN A1 on the Arduino UNO.
int UpperThreshold = 550;         // Determine which Signal to "count as a beat", and which to ignore.
int LowerThreshold = 500;

int cntHB = 0;                     // Variable for counting the number of heartbeats.
boolean ThresholdStat = true;     // Variable for triggers in calculating heartbeats.
int BPMval = 0;                   // Variable to hold the result of heartbeats calculation.

int x=0;            // Variable axis x graph values to display on OLED
int y=0;            // Variable axis y graph values to display on OLED
int lastx=0;        // The graph's last x axis variable value to display on the OLED
int lasty=0;        // The graph's last y axis variable value to display on the OLED

// 'Heart_Icon', 16x16px - I drew this heart icon at: http://dotmatrixtool.com/
const unsigned char Heart_Icon [] PROGMEM = {
  0x00, 0x00, 0x18, 0x30, 0x3c, 0x78, 0x7e, 0xfc, 0xff, 0xfe, 0xff, 0xfe, 0xee, 0xee, 0xd5, 0x56, 
  0x7b, 0xbc, 0x3f, 0xf8, 0x1f, 0xf0, 0x0f, 0xe0, 0x07, 0xc0, 0x03, 0x80, 0x01, 0x00, 0x00, 0x00
};

// Setup function
void setup() {
  pinMode(LED_A1,OUTPUT);  // Set LED_3 PIN as Output.
  Serial.begin(9600);      // Set up Serial Communication at a certain speed.
  
  // SSD1306_SWITCHCAPVCC = generate display voltage from 3.3V internally
  // Address 0x3C for 128x32 and Address 0x3D for 128x64.
  // But on my 128x64 module the 0x3D address doesn't work. What works is the 0x3C address.
  // So please try which address works on your module.
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { 
    Serial.println(F("SSD1306 allocation failed"));
    for(;;); //--> Don't proceed, loop forever
  }

// Show initial display buffer contents on the screen
  // the library initializes this with an Adafruit splash screen.
  display.display();
  delay(1000);

// Displays BPM value reading information
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(0, 12); //--> (x position, y position)
  display.print("     Please wait");
  display.setCursor(0, 22); //--> (x position, y position)
  display.print("     10  seconds");
  display.setCursor(0, 32); //--> (x position, y position)
  display.print("       to get");
  display.setCursor(0, 42); //--> (x position, y position)
  display.print(" the Heart Rate value");
  display.display(); 
  delay(3000);

// Displays the initial display of BPM value
  display.clearDisplay(); //--> for Clearing the display
  display.drawBitmap(0, 47, Heart_Icon, 16, 16, WHITE); //--> display.drawBitmap(x position, y position, bitmap data, bitmap width, bitmap height, color)
  display.drawLine(0, 43, 127, 43, WHITE); //--> drawLine(x1, y1, x2, y2, color)
  display.setTextSize(2);
  display.setTextColor(WHITE);
  display.setCursor(20, 48); //--> (x position, y position)
  display.print(": 0 BPM");
  display.display();

Serial.println();
  Serial.println("Please wait 10 seconds to get the BPM Value");
}
void loop() {
  GetHeartRate(); // Calling the GetHeartRate() subroutine
}

void GetHeartRate() {
  // Process of reading heart rate.
  unsigned long currentMillisGetHR = millis();

if (currentMillisGetHR - previousMillisGetHR >= intervalGetHR) {
    previousMillisGetHR = currentMillisGetHR;

PulseSensorSignal = analogRead(PulseSensorHRWire);

if (PulseSensorSignal > UpperThreshold && ThresholdStat == true) {
      cntHB++;
      ThresholdStat = false;
      digitalWrite(LED_A1, HIGH);
    }

if (PulseSensorSignal < LowerThreshold) {
      ThresholdStat = true;
      digitalWrite(LED_A1, LOW);
    }

DrawGraph(); // Calling the DrawGraph() subroutine
  }

// Process for getting the BPM value.
  unsigned long currentMillisResultHR = millis();

if (currentMillisResultHR - previousMillisResultHR >= intervalResultHR) {
    previousMillisResultHR = currentMillisResultHR;

BPMval = cntHB * 6; // The taken heart rate is for 10 seconds. So to get the BPM value, the total heart rate in 10 seconds x 6.
    Serial.print("BPM : ");
    Serial.println(BPMval);

display.fillRect(20, 48, 108, 18, BLACK);

display.drawBitmap(0, 47, Heart_Icon, 16, 16, WHITE);

display.drawLine(0, 43, 127, 43, WHITE);

display.setTextSize(2);
    display.setTextColor(WHITE);
    display.setCursor(20, 48);
    display.print(": ");
    display.print(BPMval);
    display.print(" BPM");
    display.display();

cntHB = 0;
  }
}

void DrawGraph() {
  // Condition to reset the graphic display if it fills the width of the OLED screen
  if (x > 127) {
    display.fillRect(0, 0, 128, 42, BLACK);
    x = 0;
    lastx = 0;
  }

// Process signal data to be displayed on OLED in graphic form
  int ySignal = PulseSensorSignal;
  if (ySignal > 850) ySignal = 850;
  if (ySignal < 350) ySignal = 350;
  int ySignalMap = map(ySignal, 350, 850, 0, 40);
  y = 40 - ySignalMap;
  // Displays the heart rate graph
  display.writeLine(lastx, lasty, x, y, WHITE);
  display.display();
  lastx = x;
  lasty = y;
  x++;
}

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

// Include Libraries

#include <SPI.h>

#include <Wire.h>

#include <Adafruit_GFX.h>

#include <Adafruit_SSD1306.h>

// OLED screen size in pixels

#define SCREEN_WIDTH 128 // OLED display width, in pixels

#define SCREEN_HEIGHT 64 // OLED display height, in pixels

// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)

#define OLED_RESET -1 // Reset pin # (or -1 if sharing Arduino reset pin)

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// Variable Declarations

unsigned long previousMillisGetHR = 0; // Store last time Millis (to get Heartbeat) was updated.

unsigned long previousMillisResultHR = 0; // Store last time Millis (to get BPM) was updated.

const long intervalGetHR = 20; // Interval for reading heart rate (Heartbeat) = 10ms.

const long intervalResultHR = 10000; // The reading interval for the result of the Heart Rate calculation is in 10 seconds.

int PulseSensorSignal; // Variable to accommodate the signal value from the sensor

const int PulseSensorHRWire = 0; // PulseSensor connected to ANALOG PIN 0 (A0 / ADC 0).

const int LED_A1 = A1; // LED to detect when the heart is beating. The LED is connected to PIN A1 on the Arduino UNO.

int UpperThreshold = 550; // Determine which Signal to "count as a beat", and which to ignore.

int LowerThreshold = 500;

int cntHB = 0; // Variable for counting the number of heartbeats.

boolean ThresholdStat = true; // Variable for triggers in calculating heartbeats.

int BPMval = 0; // Variable to hold the result of heartbeats calculation.

int x=0; // Variable axis x graph values to display on OLED

int y=0; // Variable axis y graph values to display on OLED

int lastx=0; // The graph's last x axis variable value to display on the OLED

int lasty=0; // The graph's last y axis variable value to display on the OLED

// 'Heart_Icon', 16x16px - I drew this heart icon at: http://dotmatrixtool.com/

const unsigned char Heart_Icon [] PROGMEM = {

0x00, 0x00, 0x18, 0x30, 0x3c, 0x78, 0x7e, 0xfc, 0xff, 0xfe, 0xff, 0xfe, 0xee, 0xee, 0xd5, 0x56,

0x7b, 0xbc, 0x3f, 0xf8, 0x1f, 0xf0, 0x0f, 0xe0, 0x07, 0xc0, 0x03, 0x80, 0x01, 0x00, 0x00, 0x00

};

// Setup function

void setup() {

pinMode(LED_A1,OUTPUT); // Set LED_3 PIN as Output.

Serial.begin(9600); // Set up Serial Communication at a certain speed.

// SSD1306_SWITCHCAPVCC = generate display voltage from 3.3V internally

// Address 0x3C for 128x32 and Address 0x3D for 128x64.

// But on my 128x64 module the 0x3D address doesn't work. What works is the 0x3C address.

// So please try which address works on your module.

if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {

Serial.println(F("SSD1306 allocation failed"));

for(;;); //--> Don't proceed, loop forever

}

// Show initial display buffer contents on the screen

// the library initializes this with an Adafruit splash screen.

display.display();

delay(1000);

// Displays BPM value reading information

display.clearDisplay();

display.setTextSize(1);

display.setTextColor(WHITE);

display.setCursor(0, 12); //--> (x position, y position)

display.print(" Please wait");

display.setCursor(0, 22); //--> (x position, y position)

display.print(" 10 seconds");

display.setCursor(0, 32); //--> (x position, y position)

display.print(" to get");

display.setCursor(0, 42); //--> (x position, y position)

display.print(" the Heart Rate value");

display.display();

delay(3000);

// Displays the initial display of BPM value

display.clearDisplay(); //--> for Clearing the display

display.drawBitmap(0, 47, Heart_Icon, 16, 16, WHITE); //--> display.drawBitmap(x position, y position, bitmap data, bitmap width, bitmap height, color)

display.drawLine(0, 43, 127, 43, WHITE); //--> drawLine(x1, y1, x2, y2, color)

display.setTextSize(2);

display.setTextColor(WHITE);

display.setCursor(20, 48); //--> (x position, y position)

display.print(": 0 BPM");

display.display();

Serial.println();

Serial.println("Please wait 10 seconds to get the BPM Value");

}

void loop() {

GetHeartRate(); // Calling the GetHeartRate() subroutine

}

void GetHeartRate() {

// Process of reading heart rate.

unsigned long currentMillisGetHR = millis();

if (currentMillisGetHR - previousMillisGetHR >= intervalGetHR) {

previousMillisGetHR = currentMillisGetHR;

PulseSensorSignal = analogRead(PulseSensorHRWire);

if (PulseSensorSignal > UpperThreshold && ThresholdStat == true) {

cntHB++;

ThresholdStat = false;

digitalWrite(LED_A1, HIGH);

}

if (PulseSensorSignal < LowerThreshold) {

ThresholdStat = true;

digitalWrite(LED_A1, LOW);

}

DrawGraph(); // Calling the DrawGraph() subroutine

}

// Process for getting the BPM value.

unsigned long currentMillisResultHR = millis();

if (currentMillisResultHR - previousMillisResultHR >= intervalResultHR) {

previousMillisResultHR = currentMillisResultHR;

BPMval = cntHB * 6; // The taken heart rate is for 10 seconds. So to get the BPM value, the total heart rate in 10 seconds x 6.

Serial.print("BPM : ");

Serial.println(BPMval);

display.fillRect(20, 48, 108, 18, BLACK);

display.drawBitmap(0, 47, Heart_Icon, 16, 16, WHITE);

display.drawLine(0, 43, 127, 43, WHITE);

display.setTextSize(2);

display.setTextColor(WHITE);

display.setCursor(20, 48);

display.print(": ");

display.print(BPMval);

display.print(" BPM");

display.display();

cntHB = 0;

}

void DrawGraph() {

// Condition to reset the graphic display if it fills the width of the OLED screen

if (x > 127) {

display.fillRect(0, 0, 128, 42, BLACK);

x = 0;

lastx = 0;

}

// Process signal data to be displayed on OLED in graphic form

int ySignal = PulseSensorSignal;

if (ySignal > 850) ySignal = 850;

if (ySignal < 350) ySignal = 350;

int ySignalMap = map(ySignal, 350, 850, 0, 40);

y = 40 - ySignalMap;

// Displays the heart rate graph

display.writeLine(lastx, lasty, x, y, WHITE);

display.display();

lastx = x;

lasty = y;

x++;

}

Uploading the Code

Connect the Arduino board to your computer using USB cable Select the board type and serial port in the Arduino IDE Click the “Upload” button to upload the code to the Arduino board. If you are interested in simulating Arduino, then you can visit this Wokwi website.

Working

After uploading the code wait a few seconds to calibrate the pulse sensor.

Place your finger on the Pulse Sensor to measure your heart rate

The OLED display should show your heart rate in beats per minute (BPM).

Heart Beat Display using Pulse Sensor with Arduino & OLED

Vehicle Monitoring With MCP2515 CAN Bus & Arduino

DIY Arduino GPS Tracker Project: Track Location Easily

ESP32 Real-time Battery Current & Power Monitoring in IoT

Ads Blocker Detected!!!

Ads Blocker Detected!!!

Heart Beat Display using Pulse Sensor with Arduino & OLED

Required Material

Pulse sensor Arduino

Pulse sensor Pinout

Pulse sensor Schematic

Pulse sensor Specs

Applications of pulse sensors

0.96″ I2C OLED Display

0.96″ I2C OLED Display Pinout

Schematic diagram – Heartbeat sensor Arduino

Code & Libraries – Pulse Sensor With Arduino & OLED

Example Code Arduino Pulse Sensor

Source Code

Working

Related Posts

Vehicle Monitoring With MCP2515 CAN Bus & Arduino

DIY Arduino GPS Tracker Project: Track Location Easily

ESP32 Real-time Battery Current & Power Monitoring in IoT

Ads Blocker Detected!!!

Ads Blocker Detected!!!