jdy40.println(packet); // println adds newline as delimiter delay(5000); // Send every 5 seconds
void processPacket(String packet) You must configure the JDY-40 for best range and low interference. Connect the module directly to your PC via a USB-Serial adapter (3.3V). Send AT commands ending with \r\n .
void loop() // Read from wireless module if (jdy40.available()) String command = jdy40.readString(); command.trim(); jdy40 arduino example best
void loop() while (jdy40.available()) char c = jdy40.read(); if (c == '\n') // End of packet processPacket(buffer); buffer = ""; else buffer += c;
void setup() pinMode(ledPin, OUTPUT); Serial.begin(9600); jdy40.begin(9600); Serial.println("JDY-40 Receiver Ready"); void loop() // Read from wireless module if (jdy40
// Create structured packet: <START;LENGTH;DATA;CHECKSUM> String payload = String(temp) + "," + String(hum); int checksum = temp + hum; // Simple numeric checksum String packet = "<" + String(payload.length()) + ";" + payload + ";" + String(checksum) + ">";
#include <SoftwareSerial.h> SoftwareSerial jdy40(2, 3); String buffer = ""; buffer = ""
The JDY-40 is a 2.4GHz RF transceiver module (similar to nRF24L01 but simpler) that operates as a transparent wireless serial bridge. Unlike Bluetooth, you don't need pairing; unlike WiFi, you don't need an IP address. You simply type on Serial on one end, and it appears on the other.