Tiago ESP

HC-SR04 with ESP8266 and TM1637 Display

In this tutorial, we’ll explore how to integrate an HC-SR04 ultrasonic sensor with an ESP8266 microcontroller and display the measured distance on a TM1637 7-segment display. The HC-SR04 sensor uses ultrasonic waves to calculate distance, and the TM1637 display makes it easy to showcase the results.

Requirements:

Understanding the Logic Level Conversion

The Wemos D1 Mini operates at 3.3V, while the TM1637 and the Ultrasonic Sensor typically works at 5V. To bridge this voltage gap, we’ll use a logic level converter to ensure proper communication between the devices.

Wiring:

  1. Connect the HC-SR04 sensor:
    • Trigger Pin to D1 (GPIO5)
    • Echo Pin to D2 (GPIO4)
  2. Connect the TM1637 display:
    • CLK Pin to D5 (GPIO14)
    • DIO Pin to D6 (GPIO12)

 

Installing Libraries:

  1. Open Arduino IDE.
  2. Go to “Sketch” -> “Include Library” -> “Manage Libraries…”
  3. Search for and install “TM1637Display” and “NewPing” libraries.

 

 

Code Implementation:

 

#include <TM1637Display.h>
#include <NewPing.h>

const int CLK_PIN = D5;  // CLK pin connected to D5 (GPIO14)
const int DIO_PIN = D6;  // DIO pin connected to D6 (GPIO12)
const int trigPin = D1;  // Trigger pin connected to D1 (GPIO5)
const int echoPin = D2;  // Echo pin connected to D2 (GPIO4)

TM1637Display display(CLK_PIN, DIO_PIN);
NewPing sonar(trigPin, echoPin, 200);

void setup() {
  Serial.begin(115200);
  display.setBrightness(5);
}

void loop() {
  delay(50);
  int distance_cm = sonar.ping_cm();
  int distance_mm = distance_cm * 10;
  display.showNumberDec(distance_mm);
  // No delays or display clearing
}

 

 

Explanation:

  • We use the TM1637Display library to control the 7-segment display and the NewPing library to interface with the HC-SR04 sensor.
  • The sonar.ping() function retrieves the distance in centimeters, which is then multiplied by 10 to convert it to millimeters.
  • The result is displayed on the TM1637 display.

Conclusion:

By following this tutorial, you can easily set up a system to measure distances using an HC-SR04 sensor, display the results on a TM1637 display, and integrate it into various projects such as distance measurement devices, obstacle detection systems, or smart home applications.