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： STM32 0.96inch RGB OLED ESP32 S3 Development Board 1.91 inch AMOLED Display Screen For Arduino LVGL With SD-Port/ QMI8658C 6-Axis Sensor Computer USB Monitor Screen Raspberry Pi Audio development board Raspberry Pi Pico 2 P2350-Plus Smart Car Kit PicoGo2 Autonomous Driving Learning Car DTM3202 Raspberry Pi 5 PCIe to M.2 NVMe SSD Adapter Board (D) HAT Pi5-2280-2242-2230 ESP32 IR Thermal Imaging Camera Spotpear Raspberry Pi 2inch LCD ESP32 IR Thermal Imaging Camera user guide Luckfox Pico Camera User Guide DeepSeek XiaoZhi AI Voice Chat Robot BOX ESP32-S3 Development Board 3.5 inch QSPI LCD N16R8 Touchscreen Display 6-Axis /Camera /SD RS485 to Ethernet Jetson Orin NX X1011 Raspberry Pi 5 PCIe to M.2 NVMe 4-Ports SSD Board HAT Pi5 Four-Times 2280 PI5 Case Magnetic Encoder Servo Motor 85KG.CM 12V/24V 360° RS485 High Precision And Large Torque

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

TAG： Raspberry Pi PICO Argon Raspberry Pi Pico 2 RP2350 Plus CV1800B XD-51 Raspberry Pi 5 PCIe M.2 Mini NVMe SSD Pi5 Active Cooler M12 High Resolution Lens 12MP 3.2mm For Raspberry Pi High Quality HQ Camera M12 1.54inch OLED Display Raspberry Pi 10.1 inch LCD Display Capacitive TouchScreen 1920x1200 Jetson Nano mini Computer PC MAX9296 GMSL Camera 2-Ch High-Speed Low-Latency Transmission Jetson Orin Nano/NX Raspberry Pi PICO RP2040-PiZero 1.3inch LCD Game Display Screen ST7789 Audio Buzzer Raspberry Pi 5 CSI Cable DeepSeek AI Voice Chat ESP32 C6 Development Board 2.06-inch AMOLED Display 410×502 2.06inch TouchScreen Programmable Watch Raspberry Pi 5 MIPI Camera Cable UART Serial Server Jetson CSI-to-HDMI Industrial USB Gen1 HUB 4U 7~36V DC power port For Multi Systems ESP32 C3 Round LCD Electronic EYE 0.71 inch Display Watch Screen GC9D01 160x160 D-Robotics RDK X3 Module Circular LCD Screen