Arduino Ethernet Shield using DHT11 Sensor & ThingSpeak problem

Using Arduino Project Guidance
1

Hello Everyone ! I started my project with Arduino and Temperature/Humidity sensor DHT11. I want values from sens to display on ThingSpeak Charts.

Project Components:

Arduino Uno Rev3

Ethernet Shield

DHT 11

There is my code:

#include "ThingSpeak.h"
    #include <SPI.h>
    #include <Ethernet.h>
    byte mac[] = { 0xFJ, 0x3C, 0xDA, 0xB7, 0xC1, 0x05};  //not importatnt for you
    EthernetClient client;

#include <DHT.h>

#include "DHT.h"

#define DHTPIN 12    

#define DHTTYPE DHT11   

DHT dht(DHTPIN, DHTTYPE);    
   

unsigned long myChannelNumber = MyChanellNumber;    //not importatnt for you
const char * myWriteAPIKey = "MyApiKey";                     //not importatnt for you

void setup() {
  Serial.begin(9600);
  dht.begin(); 
  Ethernet.begin(mac);
  ThingSpeak.begin(client);
}

void loop() {
  float t = dht.readTemperature();
  float h = dht.readHumidity();

  Serial.println("======================================"); 
  Serial.println("Weather condictions"); 
  Serial.print("Temperature= ");
  Serial.print(t);
  Serial.println(" C");
  Serial.print("Humidity= ");
  Serial.print(h);
  Serial.println(" %"); 
  Serial.println(); 

  ThingSpeak.writeField(myChannelNumber, 1, t, myWriteAPIKey);
  ThingSpeak.writeField(myChannelNumber, 2, h, myWriteAPIKey);
  delay(20000); 
}

Problem is with values. Serial Monitor and ThingSpeaks Field 1 Chart show me NaN (Not a Number) value. Ethernet connection was good and ThingSpeak will show any other value but not humidity and Temperature.

I tried everything:

  1. I checked out my connection. Countless times ! No problem.

  2. Try this code without Ethernet & ThingSpeak functions, only with DHT11 and Serial Monitor ,it worked without problem (showing values)!

  3. I tried ->float t = dht.readTemperature();
    String temp = String(t);
    ThingSpeak.writeField(myChannelNumber, 1, temp, myWriteAPIKey);
    String doesn´t worked !

  4. I was reading forums with similar issues. And nothing for me.

I will be grateful for any answer. Thanks.

2

The Ethernet shield uses SPI which uses pin 12 so you can't use that pin for DHT

3

Thanks a lot that halped.
But now I have a problem with ThingSpeak charts. Only one field is receiving data. Temperature is showing values but Humidty is stuck. I donˇt know why. A little moment worked just fine but now only Field one displays data.