@AWI, @mfalkvidd Thank you for your time trying to help me.

I just found a Modified SD library to use pins A0-A3 for software SPI. I got it to work!!! So happy.

If anyone interests, the link is below:

Modified SD library to use pins A0-A3 for software SPI
0_1475856752676_SD-hardcode-use-pins-A0-A3.zip

@AWI, @mfalkvidd Thank you for your time trying to help me.

I just found a Modified SD library to use pins A0-A3 for software SPI. I got it to work!!! So happy.

If anyone interests, the link is below:

Modified SD library to use pins A0-A3 for software SPI
0_1475856752676_SD-hardcode-use-pins-A0-A3.zip

Is my send routine from the arduino + nRF24L01 + sensor correct?

send(msgvolt.setDestination(DESTINATION_NODE).set(dadosenviados, 2), 1);

Or:

send(msgvolt.set(dadosenviados, 2),  1);

And the receive routine from the arduino + nRF24L01 ?

void receive(const MyMessage &msgvolt) {

  if (msgvolt.type == V_VOLTAGE) {
      
 dadosenviados = msgvolt.getFloat();

Serial.print("Incoming");
Serial.println(msgvolt.getFloat());
Serial.println(dadosenviados);
}

The configuration of the arduino + nRF24L01 + sensor:

#define MY_DEBUG 
#define MY_DEBUG_VERBOSE_RF24
#define MY_RADIO_NRF24

#define MY_NODE_ID 10

#define MY_RF24_CE_PIN 9
#define MY_RF24_CS_PIN 10
#define MY_RF24_PA_LEVEL RF24_PA_LOW
#define MY_RF24_PA_LEVEL_GW RF24_PA_LOW
#define MY_RF24_CHANNEL 76
#define MY_RF24_DATARATE RF24_250KBPS

#include <SPI.h>
#include <MySensors.h>

The configuration of the arduino + nRF24L01:

#define MY_DEBUG
#define MY_RADIO_NRF24
#define MY_DEBUG_VERBOSE_RF24

#define MY_GATEWAY_SERIAL
#define MY_NODE_ID 0

#define MY_RF24_CE_PIN 9
#define MY_RF24_CS_PIN 10
#define MY_RF24_PA_LEVEL RF24_PA_HIGH
#define MY_RF24_PA_LEVEL_GW RF24_PA_LOW
#define MY_RF24_CHANNEL 76
#define MY_RF24_DATARATE RF24_250KBPS


#include <MySensors.h>
#include <LiquidCrystal.h>
#include <SPI.h>

Hello! Hm, I removed the digitalWrite and I don't undestand why it doesn't get the data. I tried to print something in the receive routine and I got nothing. What do you mean about special case?

Thanks for the time spent with me.

Ok, I'm going to erase the void incomingMessage(const MyMessage &msgvolt) and the request(4, V_VOLTAGE, 10).
Also no savestate.

I tried to store in a global variable and display, but I didn't understand It, how do I read!?

void receive(const MyMessage &msgvolt) {
  if (msgvolt.type==V_VOLTAGE) {
    digitalWrite(msgvolt.sensor, msgvolt.getFloat());
  
 dadosenviados = msgvolt.getFloat();


Serial.println(msgvolt.getFloat());
Serial.println(dadosenviados);
Serial.println(msgvolt.data);
}

This is what I'm getting in the serial:

Node:

Battery Voltage: 8.68 V
RF24:stop listening
RF24:write register, reg=0, value=14
RF24:open writing pipe, recipient=0
RF24:write register, reg=10, value=0
RF24:write register, reg=16, value=0
RF24:send message to 0, len=12
RF24:flushTX
RF24:write register, reg=7, value=48
RF24:start listening
RF24:write register, reg=0, value=15
RF24:write register, reg=10, value=10
TSP:MSG:SEND 10-10-0-0 s=4,c=1,t=38,pt=7,l=5,sg=0,ft=0,st=ok:8.68
RF24:read message, len=12
RF24:write register, reg=7, value=64
TSP:MSG:READ 0-0-10 s=4,c=1,t=38,pt=7,l=5,sg=0:8.68
Battery Voltage: 8.69 V

Gateway:

10;4;1;0;38;8.68
0;255;3;0;9;TSP:MSG:READ 10-10-0 s=4,c=1,t=38,pt=7,l=5,sg=0:8.68
0;255;3;0;9;TSP:MSG:ACK msg
0;255;3;0;9;TSP:MSG:SEND 0-0-10-10 s=4,c=1,t=38,pt=7,l=5,sg=0,ft=0,st=ok:8.68
10;4;1;0;38;8.68

Please, someone tell me how to get the voltage that i'm receiving. I've tried many things, I don't know why this doesn't work.

msgvolt.getFloat();

I can see the battery in the gateway through serial, but I don't know how to get it to show on the LCD.

Node:

#define MY_DEBUG 
#define MY_DEBUG_VERBOSE_RF24
#define MY_RADIO_NRF24
#define DESTINATION_NODE 0      
#define MY_NODE_ID 10
#define MY_PARENT_NODE_ID  0
#define MY_PARENT_NODE_IS_STATIC
#define MY_RF24_CE_PIN 9
#define MY_RF24_CS_PIN 10
#define MY_RF24_PA_LEVEL RF24_PA_LOW
#define MY_RF24_PA_LEVEL_GW RF24_PA_LOW
#define MY_RF24_CHANNEL 76
#define MY_RF24_DATARATE RF24_250KBPS


#include <SPI.h>
#include <MySensors.h>


int sensorTensaoDC = A0;
float valorTensaoDC;
int amostragem = 1000;
float mediaTotalTensaoDC = 0;
float R1 = 28000.0;  
float R2 = 7600.0;
int sensorValue_aux = 0;
float voltsporUnidade = 0.005278592; // 5%1023

float dadosenviados;


MyMessage msgvolt(4, V_VOLTAGE);

void setup()  
{
  analogReference(DEFAULT);
  pinMode(A0, INPUT);
}

void presentation() {
   sendSketchInfo("Battery Meter", "1.0");
   present(4, S_MULTIMETER, "Voltage", true);
}

void loop()
{
   mediaTotalTensaoDC = 0;
  for(int i=0; i < amostragem ; i++)
  {
    valorTensaoDC = analogRead(sensorTensaoDC);

    valorTensaoDC =(valorTensaoDC*voltsporUnidade);
    mediaTotalTensaoDC = mediaTotalTensaoDC+ (valorTensaoDC / (R2/(R1+R2)));
  }
  dadosenviados = mediaTotalTensaoDC / amostragem;
  
  
   Serial.print("Battery Voltage: ");
   Serial.print(dadosenviados);
   Serial.println(" V");

 send(msgvolt.setDestination(DESTINATION_NODE).set(dadosenviados, 2), 1);
  wait(2000);

}

Gateway:

#define MY_DEBUG
#define MY_RADIO_NRF24
#define MY_GATEWAY_SERIAL
#define MY_NODE_ID 0
#define DESTINATION_NODE 10 
#define MY_RF24_CE_PIN 9
#define MY_RF24_CS_PIN 10
#define MY_RF24_PA_LEVEL RF24_PA_LOW
#define MY_RF24_PA_LEVEL_GW RF24_PA_LOW
#define MY_RF24_CHANNEL 76
#define MY_RF24_DATARATE RF24_250KBPS

#include <MySensors.h>
#include <LiquidCrystal.h>
#include <SPI.h>

float dadosenviados = 0;

MyMessage msgvolt(4, V_VOLTAGE);

LiquidCrystal lcd(3, 2, 7, 6, 5, 4);

void setup()  
{
  lcd.begin(20, 4);
  lcd.clear();
  lcd.setCursor(5, 0);
  lcd.print("Teste 1.6");
  delay(5000);
  lcd.setCursor(3, 2);
  lcd.print("Carregando...");
  delay(5000);
  lcd.clear();
}

void presentation() {
      sendSketchInfo("Battery Meter", "2.0");
      present(4, S_MULTIMETER);
}

void receive(const MyMessage &msgvolt) {
  saveState(msgvolt.sensor, msgvolt.getFloat());
 dadosenviados = msgvolt.getFloat();
request(4, V_VOLTAGE, 10);

}         

void incomingMessage(const MyMessage &msgvolt) {

request(4, V_VOLTAGE, 10);
dadosenviados = msgvolt.getFloat();

    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("TENSAO");
    lcd.setCursor(7, 0);
    lcd.print(dadosenviados);
    lcd.print("VOLTS");
    lcd.setCursor(0, 1);
    lcd.print(msgvolt.getFloat());
    wait(1000);
      Serial.print("Battery Voltage: ")`;
   Serial.print(dadosenviados);
   Serial.println(" V");
}

void loop() {
}

Is that how I send ? Can I use BINARY to my hall effect sensor? I'm using the digital pin to count every time it passes through a magnet.

MyMessage msg(NODE_ID, V_STATUS);

float value = 0;

void presentation()
{
    present(NODE_ID, S_BINARY);
}

void loop()
{
    send(msg.set(value));
}

Is that how I receive?

void receive(const MyMessage &message) {
    // Handle incoming message
}

I have pins and I have already done this.

Hey. I don't have I2C interface. Do I need it?

I have one like this, 20x4:

Ok, I'm getting there. I appreciate your advices, thanks.
Now I can see the battery level in the serial. But I didn't understand how to receive the battery level in the gateway to show on my LCD display.

Gateway ok:

0;255;3;0;9;Starting gateway (RNNGA-, 2.0.0)
0;255;3;0;9;TSM:INIT
0;255;3;0;9;TSM:RADIO:OK
0;255;3;0;9;TSM:GW MODE
0;255;3;0;9;TSM:READY
0;255;3;0;14;Gateway startup complete.
0;255;0;0;18;2.0.0
0;255;3;0;9;No registration required
0;255;3;0;9;Init complete, id=0, parent=0, distance=0, registration=1
0;255;3;0;9;TSP:MSG:READ 10-10-255 s=255,c=3,t=7,pt=0,l=0,sg=0:
0;255;3;0;9;TSP:MSG:BC
0;255;3;0;9;TSP:MSG:FPAR REQ (sender=10)
0;255;3;0;9;TSP:CHKUPL:OK (FLDCTRL)
0;255;3;0;9;TSP:MSG:GWL OK
0;255;3;0;9;TSP:MSG:SEND 0-0-10-10 s=255,c=3,t=8,pt=1,l=1,sg=0,ft=0,st=ok:0
0;255;3;0;9;TSP:MSG:READ 10-10-0 s=255,c=3,t=24,pt=1,l=1,sg=0:1
0;255;3;0;9;TSP:MSG:PINGED (ID=10, hops=1)
0;255;3;0;9;TSP:MSG:SEND 0-0-10-10 s=255,c=3,t=25,pt=1,l=1,sg=0,ft=0,st=ok:1
0;255;3;0;9;TSP:MSG:READ 10-10-0 s=255,c=3,t=15,pt=6,l=2,sg=0:0100
0;255;3;0;9;TSP:MSG:SEND 0-0-10-10 s=255,c=3,t=15,pt=6,l=2,sg=0,ft=0,st=ok:0100
0;255;3;0;9;TSP:MSG:READ 10-10-0 s=255,c=0,t=17,pt=0,l=5,sg=0:2.0.0
10;255;0;0;17;2.0.0
0;255;3;0;9;TSP:MSG:READ 10-10-0 s=255,c=3,t=6,pt=1,l=1,sg=0:0
10;255;3;0;6;0
0;255;3;0;9;TSP:MSG:READ 10-10-0 s=255,c=3,t=11,pt=0,l=13,sg=0:Battery Meter
0;255;3;0;9;TSP:MSG:READ 10-10-0 s=255,c=3,t=12,pt=0,l=3,sg=0:1.0
0;255;3;0;9;TSP:MSG:READ 10-10-0 s=255,c=3,t=26,pt=1,l=1,sg=0:2
0;255;3;0;9;TSP:MSG:SEND 0-0-10-10 s=255,c=3,t=27,pt=1,l=1,sg=0,ft=0,st=ok:1

Node ok:

Starting sensor (RNNNA-, 2.0.0)
TSM:INIT
RF24:write register, reg=0, value=14
RF24:read register, reg=6, value=35
RF24:flushRX
TSM:RADIO:OK
RF24:start listening
RF24:write register, reg=10, value=10
TSP:ASSIGNID:OK (ID=10)
TSM:FPAR
RF24:stop listening
RF24:write register, reg=0, value=14
RF24:open writing pipe, recipient=255
RF24:write register, reg=10, value=255
RF24:send message to 255, len=7
RF24:flushTX
RF24:MAX_RT
TSP:MSG:READ 0-0-10 s=255,c=3,t=8,pt=1,l=1,sg=0:0
TSP:MSG:FPAR RES (ID=0, dist=0)
TSP:MSG:FPAR (PPAR FOUND)
TSP:MSG:PAR OK (ID=0, dist=1)
TSM:FPAR:OK
TSM:ID
TSM:CHKID:OK (ID=10)
TSM:UPL
TSP:PING:SEND (dest=0)
TSP:MSG:PONG RECV (hops=1)
TSP:CHKUPL:OK
TSM:UPL:OK
TSM:READY
Init complete, id=10, parent=0, distance=1, registration=1
Battery Voltage: 0.00 V
Battery Voltage: 5.91 V
Battery Voltage: 5.91 V

I'm trying to do the battery level example and I'm getting this:

Starting sensor (RNNNA-, 2.0.0)
TSM:INIT
TSM:RADIO:OK
TSP:ASSIGNID:OK (ID=10)
TSM:FPAR
TSP:MSG:SEND 10-10-255-255 s=255,c=3,t=7,pt=0,l=0,sg=0,ft=0,st=bc:
TSP:MSG:READ 10-10-255 s=255,c=3,t=7,pt=0,l=0,sg=0:
TSP:MSG:BC
TSM:FPAR
TSP:MSG:SEND 10-10-255-255 s=255,c=3,t=7,pt=0,l=0,sg=0,ft=0,st=bc:
TSP:MSG:READ 10-10-255 s=255,c=3,t=7,pt=0,l=0,sg=0:
TSP:MSG:BC
TSM:FPAR
TSP:MSG:SEND 10-10-255-255 s=255,c=3,t=7,pt=0,l=0,sg=0,ft=0,st=bc:
TSM:FPAR
TSP:MSG:SEND 10-10-255-255 s=255,c=3,t=7,pt=0,l=0,sg=0,ft=0,st=bc:
!TSM:FPAR:FAIL
!TSM:FAILURE
TSM:PDT

What does it mean? Why can't I read the serial messages?