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： Raspberry Pi 13.3 inch DSI MIPI Display 13.3inch LCD Capacitive TouchScreen 1920x1080 Raspberry Pi 5 PD Power 1.28inch Round LCD 2.13Inch E-Paper ESP32-S3 0.85inch LCD Raspberry Pi USB Camera 12MP IMX378 30fps onboard dual microphones Also For Jeston / RDK USB TO 2.5G Ethernet Port Converter RJ45 RTL8156B Driver-Free For Windows/macOS/Linux/Android Milk-V Duo HUB PoE Power Supply PI5 ABS Case ESP32-S3 1.14inch LCD wide dynamic range Luckfox Pico ESP32 S3 N16R8 Development board 1.9 inch LCD Display 1.9inch TouchScreen 170&times;320 SD-Port RGB LED QMI8658 6-Axis ST7789 CST816 JETSON NANO MINI Fan ESP32-S3 AI RGB Matrix Driver Board Dual Microphone DeepSeek 101M-8001280-IPS-CT-K User Guide Raspberry Pi 5 DeepSeek AI Voice Chat ESP32 S3 Development Board 2.06-inch AMOLED Display 410×502 2.06inch TouchScreen Programmable Watch Raspberry Pi Prism

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

TAG： Raspberry Pi 4 Model B 1GB DeepSeek AI Voice Chat ESP32 Development Board 3.5 inch TouchScreen Display 320x480 Raspberry Pi Pico 1.28inch USB-CAN-B XIAO Round 1.28inch Capacitive Touch LCD Display 240×240 screen RTC watch SeeedStudio Raspberry Pi 5 Case Raspberry Pi Camera Module 2MP IMX290 Distortion Free Excellent Low Light Performance MINI linux board Raspberry Pi 5 Official Red-White Case ESP32 Display Raspberry Pi 4.3 inch DSI IPS-LCD QLED Display MIPI 800x480 Touchscreen DeepSeek Chat Robot ESP32-S3 1.54 inch LCD N16R8 MUMA Development Board Display Screen Wifi Weather Station TimeClock CPU Monitor Screen CAN Bus Breakout Board SeeedStudio-XIAO QTPy MCP2515 SN65HVD230 Raspberry Pi ESP32 Thermal imaging camera DeepSeek ESP32-S3 Voice Chat Robot ESP32 Ethernet Computer AI Deepseek Mechanical Voice Keyboard Xiaozhi LCD Screen keys Secondary Display SpotPear