void loop() isnan(t)) Serial.println("Sensor error"); else Serial.print("Temp: "); Serial.print(t); Serial.print(" C, Hum: "); Serial.print(h); Serial.println(" %");
#include <SoftwareSerial.h> #include <DHT.h>
Before wiring the components, it is critical to understand the power requirements and pin functions of the JDY-40. Key Specifications 2.4 GHz
The JDY-40 is a half-duplex, 2.4GHz wireless transceiver module. Unlike the nRF24L01, which requires managing 20+ registers via SPI, the JDY-40 communicates over . To your Arduino, it looks exactly like a wire replacement. jdy40 arduino example best
// Prepare JDY-40 (connected to hardware serial pins 0/1) pinMode(2, OUTPUT); // SET pin digitalWrite(2, LOW); // Enter AT mode (for configuring) // We'll set the channel and ID inside the loop, before each transmission.
The is a versatile 2.4GHz wireless serial transceiver module that stands out for its simplicity, long-range capabilities (up to 120 meters), and built-in GPIO control modes . Unlike standard Bluetooth modules (like the HC-05) that typically have a 10m range, the JDY-40 acts more like a wireless serial cable, making it one of the best choices for long-distance Arduino projects. Key Specifications Operating Frequency: 2.4GHz Range: Up to 120 meters (line of sight)
If you have searched for , you are likely frustrated with vague datasheets and broken English translations. This article will provide you with the definitive guide to wiring, coding, and optimizing the JDY-40 for real-world projects. void loop() isnan(t)) Serial
| Module | Frequency | Complexity | Range | Cost (approx.) | |--------|-----------|------------|-------|----------------| | JDY-40 | 2.4 GHz | Very low | 100m | $2-3 | | nRF24L01 | 2.4 GHz | Medium (SPI) | 100m | $1-2 | | HC-12 | 433 MHz | Low (UART) | 1000m | $4-5 |
// RX on Pin 2 (connect to JDY-40 TX), TX on Pin 3 (connect to JDY-40 RX) SoftwareSerial jdySerial( setup() Serial.begin( ); jdySerial.begin( );
void loop() { // 1. Handle PC -> JDY-40 Traffic if (Serial.available()) { String command = Serial.readStringUntil('\n'); command.trim(); To your Arduino, it looks exactly like a wire replacement
1200 bps to 115200 bps (Default is 9600 bps) Communication Distance: Up to 120 meters in open spaces
The JDY-40 turns a complex wireless link into a simple serial connection. Use 3.3V, match baud rates, and you’ll have two Arduinos talking in under 5 minutes.
The trick is that the JDY‑40 only listens to the currently set channel and ID. However, by switching the hub’s ID on the fly, you can address individual remotes.
Unlike power-hungry Wi-Fi modules or complex Bluetooth mesh networks, the JDY-40 acts as a transparent wireless cable. If you can use Serial.print() and Serial.read() , you can build long-range wireless projects with this hardware.