🔹 What is nRF24L01?

The nRF24L01 is a low-power, highly integrated 2.4 GHz wireless transceiver module developed by Nordic Semiconductor. It is commonly used in wireless communication applications like remote sensors, RC systems, and Internet of Things (IoT) networks.

🔹 What is DHT22?

The DHT22, also known as AM2302, is a basic digital temperature and humidity sensor. It uses a capacitive humidity sensor and a thermistor to measure the surrounding air.

🔹 Using nRF24L01 and DHT22 Together

Combining the nRF24L01 and DHT22 allows you to create wireless environmental monitoring systems. A microcontroller like Arduino reads temperature and humidity data from the DHT22 and sends it wirelessly via the nRF24L01 to another module or a central hub.

🔹 Simple Arduino Connection Example

Here’s how to connect the DHT22 and nRF24L01 to an Arduino:

• DHT22: VCC to 5V, GND to GND, Data to digital pin (e.g., D2)
• nRF24L01: CE to D9, CSN to D10, SCK to D13, MOSI to D11, MISO to D12, VCC to 3.3V

Note: Use a capacitor (10µF) across VCC and GND of nRF24L01 to avoid power spikes.

🔹 Sample Arduino Code (Sender)

#include <SPI.h>
#include <nRF24L01.h>
#include <RF24.h>
#include <DHT.h>

#define DHTPIN 2
#define DHTTYPE DHT22

RF24 radio(9, 10);
const byte address[6] = "00001";
DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(9600);
  radio.begin();
  radio.openWritingPipe(address);
  radio.setPALevel(RF24_PA_LOW);
  radio.stopListening();
  dht.begin();
}

void loop() {
  float h = dht.readHumidity();
  float t = dht.readTemperature();
  float data[2] = {t, h};
  radio.write(&data, sizeof(data));
  delay(2000);
}

🔹 Conclusion

The nRF24L01 and DHT22 are an ideal combination for building low-cost, reliable wireless environmental monitoring systems. Their integration provides valuable insights into ambient conditions while supporting scalable wireless networks — making them favorites in IoT development and smart sensing applications.