Auto-pairing. Two modules at the same RF channel and baud rate automatically connect.
Step 2: Best Arduino Code Example for Master-Slave Communication
The Arduino receives data wirelessly from a phone/PC and sends it back (echo) or prints it to the Serial Monitor. jdy40 arduino example best
This example demonstrates real-world, bidirectional sensor transmission with error resistance. It avoids the blocking delay() function, allowing your microcontroller to read sensors locally while waiting for incoming packets.
void setup() Serial.begin(9600); // Communication with PC (Serial Monitor) Serial1.begin(9600); // Communication with JDY-40 Auto-pairing
Think of it as a wireless serial cable. Whatever data you send from your Arduino's TX pin to the JDY-40's RX pin is transmitted "over the air" and will appear on the RX pin of the receiving module's connected Arduino. In its default transparent transmission mode , you don’t need to worry about packets, addresses, or acknowledgments; the module handles everything automatically.
void loop() buttonState = digitalRead(buttonPin); Whatever data you send from your Arduino's TX
To ensure two JDY-40 modules communicate effectively, they must share the same and Device ID (D_ID) . This sketch programmatically configures the module using SoftwareSerial.
Limitations
If you have multiple sets of JDY-40s nearby, change the channel and address:
