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： ESP32 ST7789 configuration Industrial RS485 Modbus RTU Relay JETSON-IO-BASE-A Jetson Nano 1.54inch OLED PC USB Monitor Screen Arduino Board Managers Tutorial User Guide HDMI to LVDS Raspberry Pi Camera V2 1.54inch LCD TouchScreen Display 240×240 ST7789S For Arduino /Raspberry Pi /ESP32 /Pico /STM32 Retail electronic Tag Industrial UART USB TO 8CH RS485 Isolated Converter For 35mm standard rail and stacked installation Sipeed NanoCluster Mini Cluster Board mini data center For Raspberry Pi CM45 / Computer /LM3H /M4N MPS2.5G Raspberry Pi 5 PCIe to NVME SSD And 2.5G Ethernet RJ45 HAT RTL8125 2280 2242 2230 BPI Raspberry Pi Pico 2 RP2350 2.8 inch LCD Capacitive TouchScreen Development Board 240x320 Display QMI8658 6-Axis /PCM5101 Audio /SD /RTC /Battery Port Milk-V Duo Code ESP32-P4-WIFI6 3.5inch LCD Display AI Development Board 320×480 3.5 inch TouchScreen Deepseek ESP32 C3 ST7735 Raspberry Pi Compute Module 4 CM4 IO Board Dual Gigabit Ethernet Mini Router Board Zero LCD HAT (A) user guide

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

TAG： Raspberry Pi 1.54 inch e-Paper HAT+ (G) E-Ink Red/Yellow/Black/White 200x200 Screen Display For Arduino /STM32/Jetson Raspberry Pi Pico 2 RP2350A Audio Box 1.85-inch LCD Round 1.85inch TouchScreen Speaker 360x360 Raspberry Pi 5 Serial ESP32-S3 3.49-inch Development Board DeepSeek AI Chat Box 3.49inch LCD Capacitive TouchScreen Display 172×640 N16R8 Luckfox Pico Core1106 RV1106 LuckFox Core3566 7inch Monitor Display ESP32 Raspberry Pi PICO LoRa UART TTL To RS232 JETSON-NANO-MINI-Board MP2.5G Raspberry Pi 5 PCIe 2.5G Ethernet Pi5 RTL8125 Raspberry Pi 5 8 inch DSI LCD Captive TouchScreen MIPI Display 1280x800 Spotpear RM500U CNV IoT EMBB 5G 4G 3G M.2 LTE-A/NSA SA GNSS DFOTA VoLTE Quectel Raspberry Pi PiKVM Type-C Power Signal Splitter With reverse power supply protection LD2410C 24GHz mmWave Radar Sensor Human Static Presence-FMCW For Arduino Home Assistant ESPHome Raspberry Pi 3D Display X1004 Raspberry Pi 5 PCIe M.2 NVMe Dual SSD Pi5 Double 2280 Raspberry Pi 14-inch Type-C/HDMI 4K TouchScreen 3840×2160 14inch computer