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 5 PCIe to M.2 SSD STM32 0.85inch LCD Computer Desktop Trinket Code Raspberry Pi Camera Case X1011 Raspberry Pi 5 PCIe to M.2 NVMe 4-Ports SSD Board HAT Pi5 Four-Times 2280 Raspberry Pi CM5 IO BASE B Mini Board a Base Development Platform Compute Module 5 IO Board with EEPROM And Encryption chip Argon DeepSeek AI Voice Chat ESP32 C6 Development Board 2.06-inch AMOLED Display 410×502 2.06inch TouchScreen Programmable Watch Raspberry Pi 0.96inch OLED Jetson Orin Milk-V Duo ESP32 ESP32-S3 Industrial 8-CH Relay IOT LAN WiFi /Bluetooth /CAN /RJ45 Ethernet /POE ESP32 Development Board C3 1.28 inch Round Rotary LCD Smart Screen 1.28inch Knob Display 240x240 LVGL for Arduino 1.28 inch Round Rotary LCD Smart Screen 1.28inch Knob Display 240x240 Option Touch/No-Touch Raspberry Pi 5 PCIe to M.2 NVMe SSD Adapter Board HAT Pi5-PCIe-MPS2242-2230-Board Industrial UART To WiFi Electronic EYE 0.71inch Round LCD Display Screen For Arduino Raspberry Pi ESP32 Pico STM32

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

TAG： Type-C Power Adapter Milk-V RJ45 Milk V Raspber Pi 5 Official Power X1203 Raspberry Pi 5 UPS Raspberry Pi 5 ICE Tower Argon THRML 60mm Radiator Cooler CPU Cooler Copper Tube Fins MPS2.5G Raspberry Pi 5 PCIe NVME SSD 2.5G Ethernet RJ45 RTL8125 2280 2242 2230 ESP32 S3 5 inch LCD 800x480 Captive TouchScreen Display LVGL HMI Sensor CAN I2C RS485 Development Board Raspberry Pi USB Camera 5MP OS05A10 Distortion-Free USB 2.0 For Jeston RDK ESP32 S3 N16R8 Development board 1.9 inch LCD Display 1.9inch TouchScreen 170×320 SD-Port RGB LED QMI8658 6-Axis ST7789 CST816 RS232 485 422 To CAN 800x480 Raspberry Pi 5 PCIe to 4-CH M.2 NVMe 4-Ports SSD Board HAT Pi5 Four-Times Development Board Raspberry Pi ST7789 ESP32 1.9inch LCD E-Paper SpotPear UGV Rover PT AI 4G 5G OpenCV Robot Car MediaPipe Jetson Orin Nano ESP32-S3