Example Code for Arduino-PWM Trigger (PWM Output)

Hardware Preparation

• Arduino board: Quantity 1
• URM37 V5.0 ultrasonic sensor (SKU:SEN0001): Quantity1
• Jumper wires: Quantity several

Software Preparation

• Arduino IDE: Download from Arduino official website

Wiring Diagram

Other Preparation Work

1. Ensure the sensor's serial level is set to TTL mode (default) using the button method described in Getting Started section.
2. Connect the hardware as per the wiring diagram.

Sample Code

// # Editor     : roker
// # Date       : 05.03.2018
// # Product name: URM V5.0 ultrasonic sensor
// # Product SKU : SEN0001
// # Version     : 1.0
// # Description:
// # The Sketch for scanning 180 degree area 2-800cm detecting range
// # The sketch for using the URM37 PWM trigger pin mode from DFRobot
// #   and writes the values to the serialport
// # Connection:
// #       Vcc (Arduino)    -> Pin 1 VCC (URM V5.0)
// #       GND (Arduino)    -> Pin 2 GND (URM V5.0)
// #       Pin 3 (Arduino)  -> Pin 4 ECHO (URM V5.0)
// #       Pin 5 (Arduino)  -> Pin 6 COMP/TRIG (URM V5.0)
// # Working Mode: PWM trigger pin  mode.
int URECHO = 3;         // PWM Output 0-50000US,Every 50US represent 1cm
int URTRIG = 5;         // trigger pin
unsigned int DistanceMeasured = 0;
void setup()
{
  //Serial initialization
  Serial.begin(9600);                        // Sets the baud rate to 9600
  pinMode(URTRIG, OUTPUT);                   // A low pull on pin COMP/TRIG
  digitalWrite(URTRIG, HIGH);                // Set to HIGH
  pinMode(URECHO, INPUT);                    // Sending Enable PWM mode command
  delay(500);
  Serial.println("Init the sensor");
}
void loop()
{
  Serial.print("Distance=");
  digitalWrite(URTRIG, LOW);
  digitalWrite(URTRIG, HIGH);              
  unsigned long LowLevelTime = pulseIn(URECHO, LOW) ;
  if (LowLevelTime >= 50000)              // the reading is invalid.
  {
    Serial.println("Invalid");
  }
  else
  {
    DistanceMeasured = LowLevelTime / 50;  // every 50us low level stands for 1cm
    Serial.print(DistanceMeasured);
    Serial.println("cm");
  }
  delay(200);
}

Result

Arduino will send the distance to master computer through serial port. The baud rate should be set to 9600.