nrf communication problem

Projects Programming
1

hi friends. at first sorry my bad english. for my wireless car project, i use nrf24l01 and gyro sensor(adxl345). i want to control car with glove. on transmitter arduino i use adxl345 and arduino nano. it creates x,y,z axis succesfully. but when i want to send this values to the reciever , i have problem. if i write "radio.write(data, sizeof(data));" it doesnt work but if i write " radio.write(data, 1); radio.write(data, 2); radio.write(data, 3);" it works but has some problems. x axis value is true, y axis value is true one times but one times its value shows zero. and z axis value is always zero.
i use arduino nano both sides, and all nrf has adapter. can someone help me

--------------Transmitter Code----------

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

#define ACC (0xA7>>1) //ADXL345 ACC address
#define A_TO_READ (6) //num of bytes we are going to read each time (two bytes for each axis)

#define CE_PIN   9
#define CSN_PIN 10

int data[3];

const uint64_t pipe = 0xE8E8F0F0E1LL;
RF24 radio(CE_PIN, CSN_PIN);
void setup()
{
 Serial.begin(9600);
 radio.begin();
 radio.openWritingPipe(pipe);
 Wire.begin();
 initAcc();
}

void loop()
{
 int hx, hy, hz;
 int acc[3];
 getAccelerometerData(acc);
 hx = acc[0];
 hy = acc[1];
 hz = acc[2];
 
   Serial.print(" X=");
   Serial.print(hx);
   Serial.print(" Y=");
   Serial.print(hy);
   Serial.print(" Z=");
   Serial.println(hz);
   delay(50);
 
 data[0] = hx;
 data[1] = hy;
 data[2] = hz;
 radio.write(data, sizeof(data));
}
.
.
.
(other functions for adxl345)

----------Reciever Code------------

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

#define CE_PIN   9
#define CSN_PIN 10
const uint64_t pipe = 0xE8E8F0F0E1LL;
RF24 radio(CE_PIN, CSN_PIN);
int data[3];

void setup()
{
  Serial.begin(9600);
 radio.begin();
 radio.openReadingPipe(1, pipe);
 radio.startListening();
}


void loop() {
 if ( radio.available() ) 
  
     radio.read( data, sizeof(data) );
     Serial.print("x :");
     Serial.println(data[0]);
     Serial.print("y :");
     Serial.println(data[1]);
     Serial.print("z :");
     Serial.println(data[2]);
   
 }
 else
 {
   Serial.println("No Signal");
 }
 
}

reciever serial1.png
reciever serial1.png904×810 5.08 KB

reciever serial2.png
reciever serial2.png904×860 8.96 KB

transmitter serial.png
transmitter serial.png904×365 5.38 KB

2

Hi,
Welcome to the forum.

Please read the first post in any forum entitled how to use this forum.
http://forum.arduino.cc/index.php/topic,148850.0.html then look down to item #7 about how to post your code.
It will be formatted in a scrolling window that makes it easier to read.

Thanks.. Tom.. :slight_smile:

3

can anybody help me?

4

Have a look at this Simple nRF24L01+ Tutorial.

You should send all the data elements in a single message. If they are all of the same type put them in an array and send the array. That is illustrated in my tutorial.

...R

5

Why do you use such convoluted code?

void loop()
{
 int hx, hy, hz;
 int acc[3];
 getAccelerometerData(acc);
 hx = acc[0];
 hy = acc[1];
 hz = acc[2];
 
   Serial.print(" X=");
   Serial.print(hx);
   Serial.print(" Y=");
   Serial.print(hy);
   Serial.print(" Z=");
   Serial.println(hz);
   delay(50);
 
 data[0] = hx;
 data[1] = hy;
 data[2] = hz;
 radio.write(data, sizeof(data));
}

You can print and send the data directly from the results array.
Why do you want to print the data before sending it, adding latency?
BTW: Why do you want your string constants to eat RAM?

void loop() {
  int acc[3];
  getAccelerometerData(acc);
  radio.write(acc, sizeof(acc));
 
  Serial.print(F(" X="));
  Serial.print(acc[0];
  Serial.print(F(" Y="));
  Serial.print(acc[1]);
  Serial.print(F(" Z="));
  Serial.println(acc[2]);
  delay(50);
}

Drop that crappy

 else
 {
   Serial.println("No Signal");
 }

If available() returns false, there is just no packet waiting, which is a rather normal state.
By flooding the 9600 Serial you will block and receiving the expected twenty packets a second
will be much harder.

Even the generated output in case of an reception ("x :1023y :1023z :1023" + CR + LF) takes nearly half
of the time you have allotted for a single packet.