Jdy40 Arduino Example Best May 2026

Here’s a more useful example: a remote temperature sensor.

Transmitter (with DHT11):

#include <DHT.h>
DHT dht(2, DHT11);
void setup() 
Serial.begin(9600);
dht.begin();

void loop() 
float temp = dht.readTemperature();
float hum = dht.readHumidity();
Serial.print(temp);
Serial.print(",");
Serial.println(hum);
delay(5000);

Receiver (Serial Plotter ready):

void setup() 
  Serial.begin(9600);
void loop() 
if (Serial.available()) 
String data = Serial.readStringUntil('\n');
Serial.println(data); // Send to Serial Plotter

Open Tools → Serial Plotter on the receiver. You’ll see a live graph of temperature and humidity – wirelessly! jdy40 arduino example best

Out of the box, the JDY-40 works. But to eliminate interference and maximize range, you must configure it via AT commands.

To enter AT mode:

Send these commands to both modules (Master and Slave):

| Command | Function | Best Setting | | :--- | :--- | :--- | | AT+RFADDR | RF Channel (0-255) | AT+RFADDR=115 (Pick a quiet channel) | | AT+RFNETID | Network ID (0-65535) | AT+RFNETID=5678 (Avoid default 0) | | AT+BAUD | UART baud rate | AT+BAUD=9600 (Most stable) | | AT+RFMD | RF Data rate | AT+RFMD=250 (250kbps = longest range) | | AT+TRPMAX | Transmit power | AT+TRPMAX=1 (Max power) | | AT+SLEEP | Power management | AT+SLEEP=0 (Disable sleep for continuous use) | Here’s a more useful example: a remote temperature sensor

Pro Tip: After setting AT+RFNETID, the modules automatically pair. No need for AT+LINK or address targeting. This is transparent broadcasting — anything one sends, all receive.

The JDY-40 is a 2.4GHz wireless transceiver designed for transparent serial transmission. Its key features include:

Because it works over UART, you can use Serial.print() to send data wirelessly.