nRF24l01+ not working

Hi there. I have been trying to get two NRF modules working for a few days now with no luck. Hopefully somebody here can steer me in the right direction. I have two brand new PA+ versions. With the antennae.

I am using two arduino UNO, no bread board NRF unit is jumpered directly into the UNO. I have tried radio pins 9 and 10, and radio pins 7 and 8. I have the RF24.h library.

The UNOs are connected to the same iMac I am running two instances of Arduino IDE to connect to the UNOs.

I keep getting connection timed out errors.Can some body look at the output and help me determine what the problem is?

/*
* 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"
#include <printf.h>

/****************** User Config ***************************/
/***      Set this radio as radio number 0 or 1         ***/
bool radioNumber = 1;

/* 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 = 1;

void setup() {
  Serial.begin(115200);
  printf_begin();
  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);
  radio.printDetails();
  
  // Open a writing and reading pipe on each radio, with opposite addresses
  if(radioNumber){
    radio.openWritingPipe(addresses[1]);
    radio.openReadingPipe(1,addresses[0]);
  }else{
    radio.openWritingPipe(addresses[0]);
    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 == 0 )
  {
    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 == 0 ){      
      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 = 0;                // Become the primary receiver (pong back)
       radio.startListening();
       
    }
  }


} // Loop

Serial output from Unit 1


RF24/examples/GettingStarted/

ROLE: Pong back

*** PRESS 'T' to begin transmitting to the other node

STATUS = 0x0e RX_DR=0 TX_DS=0 MAX_RT=0 RX_P_NO=7 TX_FULL=0
RX_ADDR_P0-1 = 0xe7e7e7e7e7 0xf0f0f0f0d2
RX_ADDR_P2-5 = 0xc3 0xc4 0xc5 0xc6
TX_ADDR = 0xe7e7e7e7e7
RX_PW_P0-6 = 0x00 0x20 0x00 0x00 0x00 0x00
EN_AA = 0x3f
EN_RXADDR = 0x02
RF_CH = 0x4c
RF_SETUP = 0x07
CONFIG = 0x0f
DYNPD/FEATURE = 0x00 0x00
Data Rate = 1MBPS
Model = nRF24L01+
CRC Length = 16 bits
PA Power = PA_MAX
*** CHANGING TO TRANSMIT ROLE -- PRESS 'R' TO SWITCH BACK

Now sending 84680...failed.

Failed, response timed out.

Now sending 85985...failed.

Failed, response timed out.


Serial output from unit 2


RF24/examples/GettingStarted/

ROLE: Pong back

*** PRESS 'T' to begin transmitting to the other node

STATUS = 0x0e RX_DR=0 TX_DS=0 MAX_RT=0 RX_P_NO=7 TX_FULL=0
RX_ADDR_P0-1 = 0x65646f4e31 0xf0f0f0f0d2
RX_ADDR_P2-5 = 0xc3 0xc4 0xc5 0xc6
TX_ADDR = 0x65646f4e31
RX_PW_P0-6 = 0x20 0x20 0x00 0x00 0x00 0x00
EN_AA = 0x3f
EN_RXADDR = 0x02
RF_CH = 0x4c
RF_SETUP = 0x03
CONFIG = 0x0f
DYNPD/FEATURE = 0x00 0x00
Data Rate = 1MBPS
Model = nRF24L01+
CRC Length = 16 bits
PA Power = PA_LOW
*** CHANGING TO TRANSMIT ROLE -- PRESS 'R' TO SWITCH BACK

Now sending 203788...failed.

Failed, response timed out.

Have a look at this Simple nRF24L01+ Tutorial.

Wireless problems can be very difficult to debug so get the wireless part working on its own before you start adding any other features.

The examples are as simple as I could make them and they have worked for other Forum members. If you get stuck it will be easier to help with code that I am familiar with. Start by getting the first example to work

There is also a connection test program to check that the Arduino can talk to the nRF24 it is connected to.

A common problem with nRF24 modules is insufficient 3.3v current from the Arduino 3.3v pin. At least for testing try powering the nRF24 with a pair of AA alkaline cells (3v) with the battery GND connected to the Arduino GND.

...R

Ok I tried both your suggestions. I used a separate power supply 2X3AAA(because I had this handy) and the instructions and code from your thread. I was unable to get successful communication between the units.

Here is the output from the simple test code on reply 29.

CheckConnection Starting

FIRST WITH THE DEFAULT ADDRESSES aft0 0x00 0x00 0x00 0x00
EN_AA		 = 0x3f
EN_RXADDR	 = 0x02
RF_CH		 = 0x4c
RF_SETUP	 = 0x07
CONFIG		 = 0x0e
DYNPD/FEATURE	 = 0x00 0x00
Data Rate	 = 1MBPS
Model		 = nRF24L01+
CRC Length	 = 16 bits
PA Power	 = PA_MAX


AND NOW WITH ADDRESS AAAxR  0x41 41 41 78 52   ON P1
 and 250KBPS data rate

STATUS		 = 0x0e RX_DR=0 TX_DS=0 MAX_RT=0 RX_P_NO=7 TX_FULL=0
RX_ADDR_P0-1	 = 0xe7e7e7e7e7 0x4141417852
RX_ADDR_P2-5	 = 0xc3 0xc4 0xc5 0xc6
TX_ADDR		 = 0xe7e7e7e7e7
RX_PW_P0-6	 = 0x00 0x20 0x00 0x00 0x00 0x00
EN_AA		 = 0x3f
EN_RXADDR	 = 0x02
RF_CH		 = 0x4c
RF_SETUP	 = 0x27
CONFIG		 = 0x0e
DYNPD/FEATURE	 = 0x00 0x00
Data Rate	 = 250KBPS
Model		 = nRF24L01+
CRC Length	 = 16 bits
PA Power	 = PA_MAX


CheckConnection Starting

FIRST WITH THE DEFAULT ADDRESSES after power on
  Note that RF24 does NOT reset when Arduino resets - only when power is removed
  If the numbers are mostly 0x00 or 0xff it means that the Arduino is not
     communicating with the nRF24

STATUS		 = 0x0e RX_DR=0 TX_DS=0 MAX_RT=0 RX_P_NO=7 TX_FULL=0
RX_ADDR_P0-1	 = 0xe7e7e7e7e7 0x4141417852
RX_ADDR_P2-5	 = 0xc3 0xc4 0xc5 0xc6
TX_ADDR		 = 0xe7e7e7e7e7
RX_PW_P0-6	 = 0x00 0x20 0x00 0x00 0x00 0x00
EN_AA		 = 0x3f
EN_RXADDR	 = 0x02
RF_CH		 = 0x4c
RF_SETUP	 = 0x07
CONFIG		 = 0x0e
DYNPD/FEATURE	 = 0x00 0x00
Data Rate	 = 1MBPS
Model		 = nRF24L01+
CRC Length	 = 16 bits
PA Power	 = PA_MAX


AND NOW WITH ADDRESS AAAxR  0x41 41 41 78 52   ON P1
 and 250KBPS data rate

STATUS		 = 0x0e RX_DR=0 TX_DS=0 MAX_RT=0 RX_P_NO=7 TX_FULL=0
RX_ADDR_P0-1	 = 0xe7e7e7e7e7 0x4141417852
RX_ADDR_P2-5	 = 0xc3 0xc4 0xc5 0xc6
TX_ADDR		 = 0xe7e7e7e7e7
RX_PW_P0-6	 = 0x00 0x20 0x00 0x00 0x00 0x00
EN_AA		 = 0x3f
EN_RXADDR	 = 0x02
RF_CH		 = 0x4c
RF_SETUP	 = 0x27
CONFIG		 = 0x0e
DYNPD/FEATURE	 = 0x00 0x00
Data Rate	 = 250KBPS
Model		 = nRF24L01+
CRC Length	 = 16 bits
PA Power	 = PA_MAX

Never mind. I added the caps to my units now they work. I'm not 100 sure that was the problem because when I went back to connect power to the RF unit after I added the cap I noticed a problem with one of the power jumpers. It might have been there fore for but I'm not sure. Either way. Problem seems to be resolved.

Thank you.

jonawadl:
I used a separate power supply 2X3AAA(because I had this handy)

That sounds worryingly like you are using 2 packs (one for each nRF24) of 3 x AAA cells which provide 4.5v volts. That is well beyond the upper 3.6v limit for the nRF24's power pin. The data pins can accept 5v.

Just use packs of 2x AA (or AAA) alkaline cells which give 3v.

Otherwise, good to hear it is working.

...R

I wasn't clear. I meant two packs of 2 3A batteries. Each NRF unit got 2 cells.

I'm back to square one though. I cannot get the units to communicate anymore. I have several smaller NRF24l01 mini that I tried using. I want to make a transmitter/receiver unit for an RC car. So I wanted a smaller unit in the receiver end. I have 8 or nine smaller units here. I tested each one to try communicate between the working NRF24l01 PA+ LNA and the NRF24L01 mini. After unsuccessfully trying the smaller units, I switched back to the larger PA+ LNA. I cannot get them to communicate anymore. I tried the connection sketch to see if the Arduino can communicate with the NRF unit. It seems to work. Here is the output.

TX

STATUS		 = 0x0e RX_DR=0 TX_DS=0 MAX_RT=0 RX_P_NO=7 TX_FULL=0
RX_ADDR_P0-1	 = 0x4141417852 0x4141417852
RX_ADDR_P2-5	 = 0xc3 0xc4 0xc5 0xc6
TX_ADDR		 = 0x4141417852
RX_PW_P0-6	 = 0x20 0x20 0x00 0x00 0x00 0x00
EN_AA		 = 0x3f
EN_RXADDR	 = 0x03
RF_CH		 = 0x4c
RF_SETUP	 = 0x07
CONFIG		 = 0x0e
DYNPD/FEATURE	 = 0x00 0x00
Data Rate	 = 1MBPS
Model		 = nRF24L01+
CRC Length	 = 16 bits
PA Power	 = PA_MAX


AND NOW WITH ADDRESS AAAxR  0x41 41 41 78 52   ON P1
 and 250KBPS data rate

STATUS		 = 0x0e RX_DR=0 TX_DS=0 MAX_RT=0 RX_P_NO=7 TX_FULL=0
RX_ADDR_P0-1	 = 0x4141417852 0x4141417852
RX_ADDR_P2-5	 = 0xc3 0xc4 0xc5 0xc6
TX_ADDR		 = 0x4141417852
RX_PW_P0-6	 = 0x20 0x20 0x00 0x00 0x00 0x00
EN_AA		 = 0x3f
EN_RXADDR	 = 0x03
RF_CH		 = 0x4c
RF_SETUP	 = 0x27
CONFIG		 = 0x0e
DYNPD/FEATURE	 = 0x00 0x00
Data Rate	 = 250KBPS
Model		 = nRF24L01+
CRC Length	 = 16 bits
PA Power	 = PA_MAX

RX

STATUS		 = 0x0e RX_DR=0 TX_DS=0 MAX_RT=0 RX_P_NO=7 TX_FULL=0
RX_ADDR_P0-1	 = 0xe7e7e7e7e7 0x4141417852
RX_ADDR_P2-5	 = 0xc3 0xc4 0xc5 0xc6
TX_ADDR		 = 0xe7e7e7e7e7
RX_PW_P0-6	 = 0x00 0x20 0x00 0x00 0x00 0x00
EN_AA		 = 0x3f
EN_RXADDR	 = 0x02
RF_CH		 = 0x4c
RF_SETUP	 = 0x07
CONFIG		 = 0x0e
DYNPD/FEATURE	 = 0x00 0x00
Data Rate	 = 1MBPS
Model		 = nRF24L01+
CRC Length	 = 16 bits
PA Power	 = PA_MAX


AND NOW WITH ADDRESS AAAxR  0x41 41 41 78 52   ON P1
 and 250KBPS data rate

STATUS		 = 0x0e RX_DR=0 TX_DS=0 MAX_RT=0 RX_P_NO=7 TX_FULL=0
RX_ADDR_P0-1	 = 0xe7e7e7e7e7 0x4141417852
RX_ADDR_P2-5	 = 0xc3 0xc4 0xc5 0xc6
TX_ADDR		 = 0xe7e7e7e7e7
RX_PW_P0-6	 = 0x00 0x20 0x00 0x00 0x00 0x00
EN_AA		 = 0x3f
EN_RXADDR	 = 0x02
RF_CH		 = 0x4c
RF_SETUP	 = 0x27
CONFIG		 = 0x0e
DYNPD/FEATURE	 = 0x00 0x00
Data Rate	 = 250KBPS
Model		 = nRF24L01+
CRC Length	 = 16 bits
PA Power	 = PA_MAX

To me this indicates that they are connecting. I have tried using power from the batteries., I have a buck converter dialed in to 3.28V and I have tried using power from the Arduino. I still have the Capacitors in place.

Is there anything in the output from the Test script that catches your eye?

I found a faulty jumper. If I move things around sometimes messages get through. I have to move into a very specific spot and it was on the Unit that was working and I never moved it since I had success in the first place. That's why I didn't find it right away.

Sorry.