HL-A838 Receiver

/*
Receiver

Before uploading these sketches to your Arduino boards, please install the "IRremote" library. You can find it in the Arduino Library Manager or on GitHub: https://github.com/z3t0/Arduino-IRremote

Once you've installed the library, upload the "Transmitter" code to one Arduino board and the "Receiver" code to another Arduino board. Wire an infrared LED to the IR_LED_PIN (pin 3) on the transmitter board, and connect the HL-A838 module's output pin to the IR_RECEIVER_PIN (pin 11) on the receiver board. Also, connect the module's VCC and GND pins to the appropriate power and ground pins on the Arduino.

The transmitter will send an NEC IR code (0x00FFA857) every 3 seconds, and the receiver will print the received signal's value on the Serial Monitor.
*/

#include <IRremote.h>

const int IR_RECEIVER_PIN = 11; // HL-A838 connected to pin 11

IRrecv irrecv(IR_RECEIVER_PIN);
decode_results results;

void setup() {
  Serial.begin(9600);
  irrecv.enableIRIn(); // Start the receiver
}

void loop() {
  if (irrecv.decode(&results)) {
    Serial.print("Received IR signal: ");
    Serial.println(results.value, HEX); // Print the received signal as a hex value
    irrecv.resume(); // Receive the next value
  }
  delay(100);
}