It has been quite some time since I’ve tinkered with an Arduino, and this go around I decided to learn something new.
The [NRF24L01](http://amzn.to/3iFalxX(opens in a new tab)) 2.4GHz Transceiver is an extremely affordable wireless chip, I managed to pickup 10 units for around $12. This chip allows sending and receiving on the 2.4GHz wireless band .
Lucky for us there is a great Arduino library just waiting to be imported, thanks maniacbug !
So what did I set out to accomplish you ask? Why a chat application of course!
Components
- ARDUINO UNO R3
- NRF24L01+ 2.4GHz Wireless RF Transceiver Module
- 400 Pin Solderless Breadboard
- Elegoo Multicolored Breadboard Jumper Wires
- Arduino w/Breadboard Holder by superwoodle
Source Code
#include <SPI.h>
#include <nRF24L01.h>
#include <RF24.h>
#define CE_PIN 9
#define CSN_PIN 10
const byte Address[5] = {'N','e','s','s','y'};
RF24 radio(CE_PIN, CSN_PIN);
String username = "";
String dataInput;
char dataToSend[32];
char dataReceived[32];
void setup() {
Serial.begin(9600);
Serial.println("Enter username...");
radio.begin();
radio.setDataRate(RF24_250KBPS);
radio.setRetries(3, 5);
radio.openWritingPipe(Address);
radio.openReadingPipe(1, Address);
}
void loop() {
// set username
while (username == "") {
if ( Serial.available() ) {
username = Serial.readStringUntil('\n');
Serial.print("Welcome ");
Serial.println(username);
}
}
// listen for radio data
radio.startListening();
if ( radio.available() ) {
// read data from radio
radio.read( &dataReceived, sizeof(dataReceived) );
Serial.println(dataReceived);
}
if( Serial.available() ) {
// stop listening on radio
radio.stopListening();
// get serial input
dataInput = "[" + username + "] " + Serial.readStringUntil('\n');
Serial.println(dataInput);
dataInput.toCharArray(dataToSend, 32);
// send data
radio.write( &dataToSend, sizeof(dataToSend) );
}
}