How to use IR Breakbeam Sensor

What is aan DFPlayerIR Pro?Breakbeam Sensor?

TheAn DFPlayerIR Probreakbeam is an upgrade of the DFPlayer Mini MP3 Player for Arduino. Itsensor is a smallpair of devices—an infrared (IR) emitter and low-pricedan MP3IR modulereceiver—that withform an internalinvisible storagebeam. ofWhen 128MB.something Thepasses modulethrough canand beblocks usedthe asbeam, athe stand-alonesensor moduledetects withthe interruption and triggers an attachedoutput battery, speaker and push buttons or used in combination with an Arduino UNO or any other with RX/TX capabilities.signal. Know More

This

tutorial

Comparing IR Breakbeam Sensor and PIR Sensor for motion detection

Feature	IR Breakbeam Sensor	PIR Sensor	Which is basedAdvantage
Detection principle	Infrared emitter + receiver; detects beam interruption.	Passive infrared; detects changes in long-wave IR (heat) in its field.	Neutral (different principles)
Sensitivity to heat sources	Unaffected by ambient heat or body temperature.	Relies on usingheat Arduinodifferences; UNO. can be affected by temperature changes.	IR Breakbeam
Detects cold/heatless objects	Yes — any object that blocks the beam will trigger it.	No — may miss objects with little thermal contrast.	IR Breakbeam
Precision / position	Very precise (exact line or plane of detection).	Less precise — detects motion in a broad PIR zone.	IR Breakbeam
Response time	Fast / near-instant when beam is interrupted.	Fast for motion but may have slight processing delay.	IR Breakbeam
False triggers (small motion / light)	Low — only triggered if beam is physically blocked.	Higher — small animal movement, drafts, or rapid temperature shifts can trigger it.	IR Breakbeam
Line-of-sight requirement	Requires clear path between emitter and receiver.	No strict line-of-sight — detects across a field of view.	PIR (for flexibility)
Coverage area	Single line/plane — narrow coverage unless multiple beams used.	Wide area coverage with a single sensor.	PIR
Power consumption	Typically low to moderate (emitter active).	Typically very low (passive sensor).	PIR
Cost & complexity	Generally simple and inexpensive; requires alignment for paired units.	Also inexpensive; easier single-unit installation.	Depends on use (neutral)
Best use cases	Object counting, door/threshold detection, conveyor interrupts, tamper lines.	Occupancy detection, motion-triggered lighting, intruder alarms over an area.	Use-case dependent

Wiring

Wiring

Receiver up(3 the sensor is less complex than the previous version with the labelled pins.

wires)

1. VINRed to 5V (Power)
2. GNDBlack to GND (Ground)
3. RXWhite to D2
pin
4. TX to D3
5. R+ to Speaker(+) red wire
6. R- to Speaker(-) black wire
7. Connect L+ & L- if you want stereo audio4

File

Rransmitter handling

(2 wires)

1. YouRed canto download our example-sounds.zip.5V
2. Connect the moduleBlack to a computer with a USBC cable.
3. Create a folder called mp3.
4. Place the mp3 files into that folder.GND

Library

DFRobot_DF1201S library will be used for this module. We have a tutorial on how to install a library here.

Get Started

#include#define <DFRobot_DF1201S.h>LEDPIN #include13
"SoftwareSerial.h"#define SoftwareSerialSENSORPIN DF1201SSerial(2,4

3)int sensorState = 0;
int lastState = 0;        

void setup() {

  pinMode(LEDPIN, OUTPUT);      
  pinMode(SENSORPIN, INPUT);     
  digitalWrite(SENSORPIN, HIGH); //RX TXturn DFRobot_DF1201Son player;the void setup(void){pullup
  
  Serial.begin(115200);
  DF1201SSerial.begin(115200);

  while (!player.begin(DF1201SSerial)) {
    Serial.println("Init failed, please check the wire connection!");
    delay(1000);
  }

  player.setVol(0);
  player.switchFunction(player.MUSIC);
  delay(2000);
  /*
    SINGLECYCLE = 1,  /**<Repeat one song 
    ALLCYCLE,         /**<Repeat all 
    SINGLE,           /**<Play one song only 
    RANDOM,           /**<Random
    FOLDER,           /**<Repeat all songs in folder 
  */
  player.setPlayMode(player.SINGLE); 
  player.setVol(20)9600);
}

void loop(){
 
  if(!player.isPlaying())sensorState = digitalRead(SENSORPIN);  // read the state of the pushbutton value:

  if (sensorState == LOW) {     // check if playerthe sensor beam is notbroken
    playingdigitalWrite(LEDPIN, player.playSpecFile(HIGH);  
  } 
  else {
    digitalWrite(LEDPIN, LOW); 
  }
  
  if (sensorState && !lastState) {
    Serial.println("/mp3/001.mp3"Unbroken");
  //play} 
  001.mp3if in(!sensorState folder&& lastState) {
    Serial.println("mp3"Broken");
  String}
  
  fileNamelastState = player.getFileName();
    Serial.print("playing: ");
    Serial.println(fileName);

  }sensorState;
}