/*
* Getting Started example sketch for nRF24L01+ radios
* This is a very basic example of how to send data from one node to another
* Updated: Dec 2014 by TMRh20
*/
#include <SPI.h>
#include "RF24.h"
/****************** User Config ***************************/
/*** Set this radio as radio number 0 or 1 ***/
bool radioNumber = ;
/* Hardware configuration: Set up nRF24L01 radio on SPI bus plus pins 7 & 8 */
RF24 radio(7,8);
/**********************************************************/
byte addresses[][6] = "1Node","2Node";
// Used to control whether this node is sending or receiving
bool role = ;
void setup()
Serial.begin(115200);
Serial.println(F("RF24/examples/GettingStarted"));
Serial.println(F("*** PRESS 'T' to begin transmitting to the other node"));
radio.begin();
// Set the PA Level low to prevent power supply related issues since this is a
// getting_started sketch, and the likelihood of close proximity of the devices. RF24_PA_MAX is default.
radio.setPALevel(RF24_PA_LOW);
// Open a writing and reading pipe on each radio, with opposite addresses
if(radioNumber)
radio.openWritingPipe(addresses[1]);
radio.openReadingPipe(1,addresses[]);
else
radio.openWritingPipe(addresses[]);
radio.openReadingPipe(1,addresses[1]);
// Start the radio listening for data
radio.startListening();
void loop()
/****************** Ping Out Role ***************************/
if (role == 1)
radio.stopListening(); // First, stop listening so we can talk.
Serial.println(F("Now sending"));
unsigned long start_time = micros(); // Take the time, and send it. This will block until complete
if (!radio.write( &start_time, sizeof(unsigned long) ))
Serial.println(F("failed"));
radio.startListening(); // Now, continue listening
unsigned long started_waiting_at = micros(); // Set up a timeout period, get the current microseconds
boolean timeout = false; // Set up a variable to indicate if a response was received or not
while ( ! radio.available() ) // While nothing is received
if (micros() - started_waiting_at > 200000 ) // If waited longer than 200ms, indicate timeout and exit while loop
timeout = true;
break;
if ( timeout ) // Describe the results
Serial.println(F("Failed, response timed out."));
else
unsigned long got_time; // Grab the response, compare, and send to debugging spew
radio.read( &got_time, sizeof(unsigned long) );
unsigned long end_time = micros();
// Spew it
Serial.print(F("Sent "));
Serial.print(start_time);
Serial.print(F(", Got response "));
Serial.print(got_time);
Serial.print(F(", Round-trip delay "));
Serial.print(end_time-start_time);
Serial.println(F(" microseconds"));
// Try again 1s later
delay(1000);
/****************** Pong Back Role ***************************/
if ( role == )
unsigned long got_time;
if( radio.available())
// Variable for the received timestamp
while (radio.available()) // While there is data ready
radio.read( &got_time, sizeof(unsigned long) ); // Get the payload
radio.stopListening(); // First, stop listening so we can talk
radio.write( &got_time, sizeof(unsigned long) ); // Send the final one back.
radio.startListening(); // Now, resume listening so we catch the next packets.
Serial.print(F("Sent response "));
Serial.println(got_time);
/****************** Change Roles via Serial Commands ***************************/
if ( Serial.available() )
char c = toupper(Serial.read());
if ( c == 'T' && role == )
Serial.println(F("*** CHANGING TO TRANSMIT ROLE -- PRESS 'R' TO SWITCH BACK"));
role = 1; // Become the primary transmitter (ping out)
else
if ( c == 'R' && role == 1 )
Serial.println(F("*** CHANGING TO RECEIVE ROLE -- PRESS 'T' TO SWITCH BACK"));
role = ; // Become the primary receiver (pong back)
radio.startListening();
// Loop
