HC-SR04 User Guide

Arduino connects ultrasonic sensor for distance measurement

Ultrasonic sensors are suitable for static distance measurement of large flat surfaces. The range of ordinary ultrasonic sensors is about 2cm-450cm, and the resolution is 3mm (the test environment is not so good, and the personal measurement is relatively stable. The distance is about 10cm-2m. If this distance is exceeded, accidental inaccuracies often occur. Of course not Eliminate technical issues.)

The test object is the SRF-04 ultrasonic sensor, which has four pins: 5v power supply pin (Vcc), trigger control terminal (Trig), receiving terminal (Echo), and ground terminal (GND)

How to use the module:

Using this module, occupies two IO ports of the single-chip microcomputer, and one IO port is used as the trigger terminal. One IO port is used as the echo PWM signal capture pin. When writing the program, firstly set the level of 8 40K cycles at the TXD pin, and the program is processed into a PWM signal and output from the RXD pin. Once an echo signal is detected, the echo signal is output for our convenience. When we use it, we only need to read the low level time (T). The echo signal is a distance object proportional to the pulse width. The distance can be calculated from the time interval between the transmitted signal and the received echo signal. Formula: uS/58=cm or uS/148=inch. The formula L=340T/2 can also be propagated in the air by sound waves. You can find L (measured distance). If no reverberation signal is detected, the module’s reverberation signal pin will output a level of about 140uS to prevent the transmitted signal from affecting the reverberation signal.

The working principle of the module:

IO trigger ranging to at least 10us high signal;

module automatically sends eight 40kHz square wave, automatically detect whether a signal return;

a signal to return to a high IO output, high duration of the ultrasonic time from launch to return.

Test distance = (time high * speed of sound (340M / S)) / 2;

Circuit connection method:

Arduino program example:

const int TrigPin = 2;
const int EchoPin = 3;
float cm;
void setup()
{
Serial.begin(9600);
pinMode(TrigPin, OUTPUT);
pinMode(EchoPin, INPUT);
}
void loop()
{
digitalWrite(TrigPin, LOW); //Send a short time pulse to TrigPin
delayMicroseconds(2);
digitalWrite(TrigPin, HIGH);
delayMicroseconds(10);
digitalWrite(TrigPin, LOW);

cm = pulseIn(EchoPin, HIGH) / 58.0; //Convert the echo time to cm
cm = (int(cm * 100.0)) / 100.0; //Keep two decimal places
Serial.print(cm);
Serial.print("cm");
Serial.println();
delay(1000);
}

Download: http://pan.baidu.com/s/1zKSbC

To：

Dear Customers, There may be a lag of several hours before we could process your order, depending on the time difference between your location and ours. Sincerely hoping your understanding!

Email(support)

services01@spotpear.com

TAG： SpotPear Magnetic Encoder Servo Motor 45KG.CM 24V 360° RS485 High Precision And Large Torque UART To CAN ESP32 C5 Development Board 1.47 inch LCD Display Screen ST7789 For WiFi6/LVGL/HMI Onborad SD-Port/RGB-LED Raspberry Pi 5 PCIe USB HUB 3.2 Gen1 HAT+ High Speed Pi5 Accelerometer i7-1165G7 Raspberry Pi Pico Raspberry Pi CM5 IO BASE A Mini Board a Base Development Platform Compute Module 5 IO Board Raspberry Pi PICO LoRa ESP32 S3 AI 0.85inch Development Board 0.85 inch DeepSeek RGB surround light Arduino IR Thermal Imaging Camera Industrial Modbus RTU 8 ch Relay Module Jetson Nano PWM Fan JETSON NANO MINI Expansion Board Code Onboard ESP32-C6 Development Board Arduino Board Managers Tutorial User Guide Python UART Communication 1.38MP Global Shutter Camera ISG1321 For Luckfox Pico Zero

Ultrasonic Wave Detector Ranging Module PICAXE Microcontroller Sensor HC SR0 for Arduino/51/STM32

TAG： ESP32-H2-MINI-1-N4 Cortex-A53 Raspberry Pi 5 Heatsink MPW2.5G Raspberry Pi 5 PCIe WiFi 7 2.5G Ethernet RJ45 RTL8125 WiFi7 WiFi6 WiFi5 XIAO-nRF52840 Sense BLE microphone Sensor Arduino MicroPython SeeedStudio Tiny SuperMini Mechanical Keyboard DeepSeek ESP32 S3 1.8 inch AMOLED Display TouchScreen AI Voice Programmable Watch DeepSeek ESP32-S3 Voice Chat Robot 1.85 inch LCD BOX Horizon Sunrise RDK X5 Dedicated Heat Dissipation Shell Aluminum Alloy Material Cooling Fan Camera Mount Raspberry Pi 21.5inch FHD LCD 1080x1920 Capacitive TouchScreen Display ESP32-S3 Development Board 1.47 inch LCD 1.47B Display 1.47inch Screen SD 172×320 RGB LED PC USB Monitor Screen 1.54inch OLED 3.5 inch LCD 1.28inch Round LCD X1202 Raspberry Pi 5 UPS Raspberry Pi Pico 2 RP2350B 7inch Capacitive TouchScreen 7 inch LCD Display Development Board 800×480 Raspberry Pi USB Camera 5MP CPU Raspberry Pi 5 PCIe M.2 5G 4G 3G SIM8262A-M2