@mfalkvidd @gohan

Just resolved the issue !

Apparently my Arduino Ide wasnt updated to the lastest version which explains why I never found the Library Manager

@mfalkvidd Ah thanks ! Also when you mean power it with 3.3V do you mean just the nrf module or the entire Pro mini board ?

@mfalkvidd I m sorry but Whats flashing a sketch ?

@mfalkvidd
Well, I do believe that is the underlying issue here. But the NRF modules can't handle VCC more than 3.3V so I took a 3.3V connection from my breakout board (CP2012) and supplied to the NRF module (Vcc pin only).
Could this be causing the issue?

@gohan Well I was gonna use the received text to test the communication itself. The whole point I got a pro mini was to connect it as a serial gateway to the RPi3 and see it on Domoticz as we discussed earlier.

@gohan
Code in Pro Mini:

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

RF24 radio(9, 10);

const byte rxAddr[6] = "00001";

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

void loop()
{
  if (radio.available())
  {
    char text[32] = {0};
    radio.read(&text, sizeof(text));
    
    Serial.println(text);
  }
}

Code in Uno:

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

RF24 radio(9, 10);

const byte rxAddr[6] = "00001";

void setup(void)
{
  radio.begin();
  //Serial.println(F("*** PRESS 'T' to begin transmitting to the other node"));
  radio.setRetries(15, 15);
  radio.openWritingPipe(rxAddr);
  
  radio.stopListening();
}

void loop(void)
{
  const char text[] = "Hello World";
  radio.write(&text, sizeof(text));
  
  delay(1500);
}

I have set the processor to 3.3V 8MHz.
I have connected the Pro mini to the computer via a CP2102 breakout board.

@gohan

I am facing an issue while sending data from an Arduino pro mini 5V to an arduino UNO. Receiving a lot of garbage from the Pro mini.
Any idea why ?

@mfalkvidd

It worked yesterday now I am back to the same problem.
What a wonder !

@mfalkvidd Haha not really a 3.3 output I changed its input voltge to 3.3 hoping it would work.

But nevertheless I managed to solve the issue.
It seems to be an error in the Hardware serial.

Refer: http://forum.arduino.cc/index.php?topic=46458.0

The code bhagman has posted worked !

@mfalkvidd

I have an arduino pro mini 5V. But I have attached a breakout CP2102 usb connection to it. On the board there is a 3.3V point which I have plugged in as Vcc to the NRF24L01+ module.

To upload the code I have selected the 5V 16Mhz as processor.

@gohan
Thanks for the code!

I have been trying to send data from an Uno to a pro mini. Unfortunately, I have been receiving symbols and gibberish on the mini as it has be assigned as a receiver.
Any clue why?
I was hoping to send the collected data from the pro mini to the RPi3 via serial gateway and then to Domoticz.