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： NVIDIA Jetson TX2 NX Module Raspberry Pi 3.97 inch e-Paper link BW 800x480 For Arduino / Jetson / STM32 /ESP32 MP2.5G Raspberry Pi 5 PCIe to 2.5G Ethernet HAT Pi5 RTL8125 Wiki User Guide 7inch Round LCD HDMI Capacitive 7 inch Touchscreen Display 1080x1080 For Raspberry Pi/Jetson Nano/mini PC 8.9inch LCD HDMI Capacitive 8.9 inch Touchscreen Display 600x1600 For Raspberry Pi/Jetson Nano/PC 5inch Raspberry Pi Pico 2 RP2350B 1.46 inch Round LCD Touch Display 412x412 HMI LVGL QMI8658 6-axis 65K Colors Raspberry Pi 21.5 inch Type C/HDMI Display Screen 1920x1080 Computer PC Phone Xbox/PS4/Switch Industrial USB TO RS485 Isolated Bidirectional Converter Original FT232RNL 2 Meters long Raspberry Pi Mini STM32 programmer Raspberry Pi 5 Raspberry Pi Triple Screen HAT UNO Minima RA4M1 ZERO Tiny SuperMini R7FA4M1 Board Compatible With R4 For Arduino Python UART Communication ESP32-S3 Industrial RS485 Development Board with WLED Strip Driver and for XiaoZhi AI Voice Interaction UART Jetson RTL8822CE 5GHz WiFi Wireless Bluetooth5 Card NGFF-M.2 RTL8822CE-CG Core

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

TAG： ESP32-S3 AI 1.54-inch (G) e-Paper Ink Screen 1.54inch Display AIoT Development Board Deepseek Raspberry Pi 5 PCIe to 4 Port 2.5G Gigabit Ethernet Adapter RJ45 Ports 3D Display Transparent Screen RS232 to CAN Arducam Arduino ATmega32U4 Raspberry Pi Pico 2 RP2350B Industrial 8-Channel Relay IOT LAN Digital Input DIO /RS485 /RJ45 Ethernet /POE Raspberry Pi 5 BBC Microbit programmable gamepad for Micro:bit Computer Monitor Screen Raspberry Pi 5 inch DSI Display MIPI LCD (C) Capacitive TouchScreen 1024x600 Core3566104000 Bus Servo DC-BUCK-Adapter 7.2V/6V Voltage mini module For SC15/SC09 Servo RM500U CNV IoT EMBB 5G 4G 3G M.2 LTE-A/NSA SA GNSS DFOTA VoLTE Quectel Jetson Xavier TX2 NX JETSON-IO-BASE-B Raspberry Pi 5 Official Original SSD NVMe PCIe Gen3 DDSM115 Servo Motor All-In-One Hub RS485 ESP32 1.9inch LCD SpeedyBee F405 V3 BLS 60A FC ESC Stack Flight Controller DJI FPV Drone Raspberry Pi