user29758: I'm a beginer, did some tests with Uno and now have a Wemos D1R2 on my hands... 
I'm building a sort of weather station that will send data to thingspeak.com and log this data there.
I managed to merge 2 examples together (1 to send data to thingspeak) and (1 to read 1 DS18B20 with onewire)
I now need to connect 2 or more DS18B20 sensors on the same Onewire BUS (I also managed to do this using this tutorial  http://arduino-info.wikispaces.com/Brick-Temperature-DS18B20#mult ), the readings come alright on serial monitor but when I try to send the readings to thingspeak a get a error:

temp_logger_multime_sensors_2:174:  error: statement cannot resolve
  address of overloaded function

Serial.print printTemperature(Probe01);
My piece of code:

/* References
    DHT11 sensor data to Thingspeak using a Wemos D1
    http://www.esp8266learning.com/dht11-sensor-data-to-thingspeak-using-a-wemos-d1.php#codesyntax_3

   Rui Santos - Complete project details at http://randomnerdtutorials.com

   YourDuino Multiple DS18B20 Temperature Sensors on 1 wire
   http://arduino-info.wikispaces.com/Brick-Temperature-DS18B20#mult
   V1.01  01/17/2013 ...based on examples from Rik Kretzinger
*/

#include <ESP8266WiFi.h>
#include <OneWire.h>
#include <DallasTemperature.h>

// replace with your channel’s thingspeak API key and your SSID and password
String apiKey = "THINGSPEAKKEY"; 
const char* ssid = "WIFINAME";
const char* password = "WIFIPASSWORD";
const char* server = "api.thingspeak.com";

/*-----( Declare Constants and Pin Numbers )-----*/
#define ONE_WIRE_BUS_PIN 5

/*-----( Declare objects )-----*/
// Setup a oneWire instance to communicate with any OneWire devices
OneWire oneWire(ONE_WIRE_BUS_PIN);

// Pass our oneWire reference to Dallas Temperature.
DallasTemperature sensors(&oneWire);

DeviceAddress Probe01 = { 0x28, 0xFF, 0x51, 0xA5, 0x61, 0x16, 0x03, 0x92 }; // probe 1
DeviceAddress Probe02 = { 0x28, 0xFF, 0xF8, 0x99, 0x52, 0x16, 0x04, 0xB1 }; // probe 2

WiFiClient client;

void setup()   /****** SETUP: RUNS ONCE ******/
{
  // start serial port to show results
    Serial.begin(115200);
  delay(10);

/*  Serial.begin(9600);
  Serial.print("Initializing Temperature Control Library Version ");
  Serial.println(DALLASTEMPLIBVERSION);
  */
  // Initialize the Temperature measurement library
  sensors.begin();

 WiFi.begin(ssid, password);

  // Connecting to WiFi network
  Serial.println();
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);

  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED)
  {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.println("WiFi connected on IP ...");
  // Printing the ESP IP address
  Serial.println(WiFi.localIP());
}  

/*-----( Declare User-written Functions )-----*/
  void printTemperature(DeviceAddress deviceAddress)
  {
  float tempC = sensors.getTempC(deviceAddress);
     if (tempC == -127.00) 
     {
     Serial.print("Error getting temperature  ");
     } 
     else
     {
     Serial.print(tempC);
     }
  }// End printTemperature

void loop()   /****** LOOP: RUNS CONSTANTLY ******/
{
  delay(1000);
  Serial.println();
  Serial.print("Number of Devices found on bus = ");  
  Serial.println(sensors.getDeviceCount());   
  Serial.print("Getting temperatures... ");  
  Serial.println();   

  // Command all devices on bus to read temperature  

  sensors.requestTemperatures();  

float StrProbe01 = printTemperature(Probe01); //THINK PROBLEM IS HERE
float StrProbe02 = printTemperature(Probe02); //AND HERE

  Serial.print("Probe 01 temperature is:   ");
    printTemperature(Probe01);  //<-- THIS PART WORKS
  Serial.println();

  Serial.print("Probe 02 temperature is:   ");
    printTemperature(Probe02);

  Serial.println();

if (client.connect(server,80)) {
  String postStr = apiKey;
  postStr +="&field1=";
  postStr += float(StrProbe01);
  postStr +="&field2=";
   postStr += float(StrProbe02);
  postStr += "\r\n\r\n";

  client.print("POST /update HTTP/1.1\n");
  client.print("Host: api.thingspeak.com\n");
  client.print("Connection: close\n");
  client.print("X-THINGSPEAKAPIKEY: "+apiKey+"\n");
  client.print("Content-Type: application/x-www-form-urlencoded\n");
  client.print("Content-Length: ");
  client.print(postStr.length());
  client.print("\n\n");
  client.print(postStr);

  Serial.print("Temperature: ");
  Serial.print printTemperature(Probe01);
  Serial.print(" degrees Celsius Humidity: ");
  Serial.print printTemperature(Probe02);
  Serial.println("Sending data to Thingspeak");
  }
  client.stop();

  Serial.println("Waiting 20 secs");
  // thingspeak needs at least a 15 sec delay be een updates
  // 20 seconds to be safe
  delay(20000);

}//--(end main loop )---

I suspect I have to transform printTemperature(Probe01); into a variable first (as you can see on the code) and use this variable on postStr += StrProbe01; as  but I tried as you can see on the code and it didnt work either. 
* UPDATE * The code below works sending data to thingspeak and serial monitor fine with 1 DS18B20
#include <ESP8266WiFi.h>
#include <OneWire.h>
#include <DallasTemperature.h>

// replace with your channel’s thingspeak API key and your SSID and password
String apiKey = "THINGSPEAKKEY"; 
const char* ssid = "WIFINAME";
const char* password = "WIFIPASSWORD";
const char* server = "api.thingspeak.com";

const char* t2 = "5";
const char* h2 = "12.34";

//START DS18B20 Stuff
// Data wire is plugged into pin D1 on the ESP8266 12-E - GPIO 5
#define ONE_WIRE_BUS 5  // DS18B20 pin

// Setup a oneWire instance to communicate with any OneWire devices (not just Maxim/Dallas temperature ICs)
OneWire oneWire(ONE_WIRE_BUS);

// Pass our oneWire reference to Dallas Temperature. 
DallasTemperature DS18B20(&oneWire);
char temperatureCString[6];
char temperatureFString[6];

//END DS18B20 stuff

WiFiClient client;

void setup() 
{
Serial.begin(115200);
delay(10);

// dht.begin();
DS18B20.begin(); // IC Default 9 bit. If you have troubles consider upping it 12. Ups the delay giving the IC more time to process the temperature measurement

WiFi.begin(ssid, password);

// Connecting to WiFi network
Serial.println();
Serial.println();
Serial.print("Connecting to ");
Serial.println(ssid);

WiFi.begin(ssid, password);

while (WiFi.status() != WL_CONNECTED) 
{
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected on IP ...");
// Printing the ESP IP address
Serial.println(WiFi.localIP());
}

void getTemperature() {
  float tempC;
  float tempF;
  do {
    DS18B20.requestTemperatures(); 
    tempC = DS18B20.getTempCByIndex(0);
    dtostrf(tempC, 2, 2, temperatureCString);
    tempF = DS18B20.getTempFByIndex(0);
    dtostrf(tempF, 3, 2, temperatureFString);
    delay(100);
  } while (tempC == 85.0 || tempC == (-127.0));
}

// runs over and over again
void loop() 
{

 getTemperature();

if (client.connect(server,80)) {
String postStr = apiKey;
postStr +="&field1=";
postStr += String(temperatureCString);
postStr +="&field2=";
postStr += String(temperatureFString);
postStr += "\r\n\r\n";

client.print("POST /update HTTP/1.1\n");
client.print("Host: api.thingspeak.com\n");
client.print("Connection: close\n");
client.print("X-THINGSPEAKAPIKEY: "+apiKey+"\n");
client.print("Content-Type: application/x-www-form-urlencoded\n");
client.print("Content-Length: ");
client.print(postStr.length());
client.print("\n\n");
client.print(postStr);

Serial.print("Temp in C: ");
Serial.print(temperatureCString);
Serial.print(" and Temp in F: ");
Serial.print(temperatureFString);
Serial.println("Sending data to Thingspeak");
}
client.stop();

Serial.println("Waiting 20 secs");
// thingspeak needs at least a 15 sec delay be een updates
// 20 seconds to be safe
delay(20000);
}

And this code works fine displaying 2 DS18B20 on serial monitor connected to 1 Onewire BUS, but I need to implement (uncomment) the thingspeak part now.
#include <ESP8266WiFi.h>
#include <OneWire.h>
#include <DallasTemperature.h>

// replace with your channel’s thingspeak API key and your SSID and password
String apiKey = "THINGSPEAKKEY"; 
const char* ssid = "WIFINAME";
const char* password = "WIFIPASSWORD";
const char* server = "api.thingspeak.com";

/*-----( Declare Constants and Pin Numbers )-----*/
#define ONE_WIRE_BUS_PIN 5

/*-----( Declare objects )-----*/
// Setup a oneWire instance to communicate with any OneWire devices
OneWire oneWire(ONE_WIRE_BUS_PIN);

// Pass our oneWire reference to Dallas Temperature.
DallasTemperature sensors(&oneWire);

DeviceAddress Probe01 = { 0x28, 0xFF, 0x51, 0xA5, 0x61, 0x16, 0x03, 0x92 }; // probe 1
DeviceAddress Probe02 = { 0x28, 0xFF, 0xF8, 0x99, 0x52, 0x16, 0x04, 0xB1 }; // probe 2

WiFiClient client;

void setup()   /****** SETUP: RUNS ONCE ******/
{
  // start serial port to show results
    Serial.begin(115200);
  delay(10);

  // Initialize the Temperature measurement library
  sensors.begin();

 WiFi.begin(ssid, password);

  // Connecting to WiFi network
  Serial.println();
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);

  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED)
  {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.println("WiFi connected on IP ...");
  // Printing the ESP IP address
  Serial.println(WiFi.localIP());

}  //--(end setup )---

/*-----( Declare User-written Functions )-----*/
  void printTemp(DeviceAddress deviceAddress)
  {
  float tempC = sensors.getTempC(deviceAddress);
     if (tempC == -127.00) 
     {
     Serial.print("Error getting temperature  ");
     } 
     else
     {
     Serial.print(tempC);
     }
  }// End printTemp

void loop()   /****** LOOP: RUNS CONSTANTLY ******/
{
  delay(1000);
  Serial.println();
  Serial.print("Number of Devices found on bus = ");  
  Serial.println(sensors.getDeviceCount());   
  Serial.print("Getting temperatures... ");  
  Serial.println();   

  // Command all devices on bus to read temperature  

  sensors.requestTemperatures();  

  Serial.print("Probe 01 temperature is:   ");
    printTemp(Probe01);
  Serial.println();

  Serial.print("Probe 02 temperature is:   ");
    printTemp(Probe02);

  Serial.println();

/*
if (client.connect(server,80)) {
  String postStr = apiKey;
  postStr +="&field1=";
  postStr += float(StrProbe01);
  postStr +="&field2=";
   postStr += float(StrProbe02);
  postStr += "\r\n\r\n";

  client.print("POST /update HTTP/1.1\n");
  client.print("Host: api.thingspeak.com\n");
  client.print("Connection: close\n");
  client.print("X-THINGSPEAKAPIKEY: "+apiKey+"\n");
  client.print("Content-Type: application/x-www-form-urlencoded\n");
  client.print("Content-Length: ");
  client.print(postStr.length());
  client.print("\n\n");
  client.print(postStr);

  Serial.print("Temperature: ");
  Serial.print printTemp(Probe01);
  Serial.print(" degrees Celsius Humidity: ");
  Serial.print printTemp(Probe02);
  Serial.println("Sending data to Thingspeak");
  }
  client.stop();

  Serial.println("Waiting 20 secs");
  // thingspeak needs at least a 15 sec delay be een updates
  // 20 seconds to be safe
  delay(20000);
 */
}//--(end main loop )---

It has all to do on generate a sort of variable (perhaps float , im not sure) and passing it as a http string
Thanks

user43070: In the code that works, you have:
if (client.connect(server,80)) {
String postStr = apiKey;
postStr +="&field1=";
postStr += String(temperatureCString);
postStr +="&field2=";
postStr += String(temperatureFString);
postStr += "\r\n\r\n";

In the code that does not work you are doing this:
if (client.connect(server,80)) {
  String postStr = apiKey;
  postStr +="&field1=";
  postStr += float(StrProbe01);
  postStr +="&field2=";
   postStr += float(StrProbe02);
  postStr += "\r\n\r\n";

Print out the both the Strings that you are sending, postStr, using Serial.print. Compare the result. I'm not at home at the moment to try it out, but I'm sure the float(StrProbe01) and float(StrProbe02) is wrong. Thingspeak explains in their guidelines what the string that you are sending should look like.

29758: <p>I'm a beginer, did some tests with Uno and now have a Wemos D1R2 on my hands... 
I'm building a sort of weather station that will send data to thingspeak.com and log this data there.
I managed to merge 2 examples together (1 to send data to thingspeak) and (1 to read 1 DS18B20 with onewire)
I now need to connect 2 or more DS18B20 sensors on the same Onewire BUS (I also managed to do this using this tutorial  <a href="http://arduino-info.wikispaces.com/Brick-Temperature-DS18B20#mult" rel="nofollow noreferrer">http://arduino-info.wikispaces.com/Brick-Temperature-DS18B20#mult</a> ), the readings come alright on serial monitor but when I try to send the readings to thingspeak a get a error:</p>

<blockquote>
  <p>temp_logger_multime_sensors_2:174:  error: statement cannot resolve
  address of overloaded function</p>
</blockquote>

<p>Serial.print printTemperature(Probe01);</p>

<p>My piece of code:
</p>

<pre class="lang-cpp prettyprint-override"><code>/* References
    DHT11 sensor data to Thingspeak using a Wemos D1
    http://www.esp8266learning.com/dht11-sensor-data-to-thingspeak-using-a-wemos-d1.php#codesyntax_3

   Rui Santos - Complete project details at http://randomnerdtutorials.com

   YourDuino Multiple DS18B20 Temperature Sensors on 1 wire
   http://arduino-info.wikispaces.com/Brick-Temperature-DS18B20#mult
   V1.01  01/17/2013 ...based on examples from Rik Kretzinger
*/

#include &lt;ESP8266WiFi.h&gt;
#include &lt;OneWire.h&gt;
#include &lt;DallasTemperature.h&gt;

// replace with your channel’s thingspeak API key and your SSID and password
String apiKey = "THINGSPEAKKEY"; 
const char* ssid = "WIFINAME";
const char* password = "WIFIPASSWORD";
const char* server = "api.thingspeak.com";

/*-----( Declare Constants and Pin Numbers )-----*/
#define ONE_WIRE_BUS_PIN 5

/*-----( Declare objects )-----*/
// Setup a oneWire instance to communicate with any OneWire devices
OneWire oneWire(ONE_WIRE_BUS_PIN);

// Pass our oneWire reference to Dallas Temperature.
DallasTemperature sensors(&amp;oneWire);

DeviceAddress Probe01 = { 0x28, 0xFF, 0x51, 0xA5, 0x61, 0x16, 0x03, 0x92 }; // probe 1
DeviceAddress Probe02 = { 0x28, 0xFF, 0xF8, 0x99, 0x52, 0x16, 0x04, 0xB1 }; // probe 2

WiFiClient client;

void setup()   /****** SETUP: RUNS ONCE ******/
{
  // start serial port to show results
    Serial.begin(115200);
  delay(10);

/*  Serial.begin(9600);
  Serial.print("Initializing Temperature Control Library Version ");
  Serial.println(DALLASTEMPLIBVERSION);
  */
  // Initialize the Temperature measurement library
  sensors.begin();

 WiFi.begin(ssid, password);

  // Connecting to WiFi network
  Serial.println();
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);

  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED)
  {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.println("WiFi connected on IP ...");
  // Printing the ESP IP address
  Serial.println(WiFi.localIP());
}  

/*-----( Declare User-written Functions )-----*/
  void printTemperature(DeviceAddress deviceAddress)
  {
  float tempC = sensors.getTempC(deviceAddress);
     if (tempC == -127.00) 
     {
     Serial.print("Error getting temperature  ");
     } 
     else
     {
     Serial.print(tempC);
     }
  }// End printTemperature

void loop()   /****** LOOP: RUNS CONSTANTLY ******/
{
  delay(1000);
  Serial.println();
  Serial.print("Number of Devices found on bus = ");  
  Serial.println(sensors.getDeviceCount());   
  Serial.print("Getting temperatures... ");  
  Serial.println();   

  // Command all devices on bus to read temperature  

  sensors.requestTemperatures();  

float StrProbe01 = printTemperature(Probe01); //THINK PROBLEM IS HERE
float StrProbe02 = printTemperature(Probe02); //AND HERE

  Serial.print("Probe 01 temperature is:   ");
    printTemperature(Probe01);  //&lt;-- THIS PART WORKS
  Serial.println();

  Serial.print("Probe 02 temperature is:   ");
    printTemperature(Probe02);

  Serial.println();

if (client.connect(server,80)) {
  String postStr = apiKey;
  postStr +="&amp;field1=";
  postStr += float(StrProbe01);
  postStr +="&amp;field2=";
   postStr += float(StrProbe02);
  postStr += "\r\n\r\n";

  client.print("POST /update HTTP/1.1\n");
  client.print("Host: api.thingspeak.com\n");
  client.print("Connection: close\n");
  client.print("X-THINGSPEAKAPIKEY: "+apiKey+"\n");
  client.print("Content-Type: application/x-www-form-urlencoded\n");
  client.print("Content-Length: ");
  client.print(postStr.length());
  client.print("\n\n");
  client.print(postStr);

  Serial.print("Temperature: ");
  Serial.print printTemperature(Probe01);
  Serial.print(" degrees Celsius Humidity: ");
  Serial.print printTemperature(Probe02);
  Serial.println("Sending data to Thingspeak");
  }
  client.stop();

  Serial.println("Waiting 20 secs");
  // thingspeak needs at least a 15 sec delay be een updates
  // 20 seconds to be safe
  delay(20000);

}//--(end main loop )---
</code></pre>

<p>I suspect I have to transform <code>printTemperature(Probe01);</code> into a variable first (as you can see on the code) and use this variable on <code>postStr += StrProbe01;</code> as  but I tried as you can see on the code and it didnt work either. </p>

<p><strong>* UPDATE *</strong> The code below works sending data to thingspeak and serial monitor fine with 1 DS18B20</p>

<pre class="lang-cpp prettyprint-override"><code>#include &lt;ESP8266WiFi.h&gt;
#include &lt;OneWire.h&gt;
#include &lt;DallasTemperature.h&gt;

// replace with your channel’s thingspeak API key and your SSID and password
String apiKey = "THINGSPEAKKEY"; 
const char* ssid = "WIFINAME";
const char* password = "WIFIPASSWORD";
const char* server = "api.thingspeak.com";

const char* t2 = "5";
const char* h2 = "12.34";

//START DS18B20 Stuff
// Data wire is plugged into pin D1 on the ESP8266 12-E - GPIO 5
#define ONE_WIRE_BUS 5  // DS18B20 pin

// Setup a oneWire instance to communicate with any OneWire devices (not just Maxim/Dallas temperature ICs)
OneWire oneWire(ONE_WIRE_BUS);

// Pass our oneWire reference to Dallas Temperature. 
DallasTemperature DS18B20(&amp;oneWire);
char temperatureCString[6];
char temperatureFString[6];

//END DS18B20 stuff

WiFiClient client;

void setup() 
{
Serial.begin(115200);
delay(10);

// dht.begin();
DS18B20.begin(); // IC Default 9 bit. If you have troubles consider upping it 12. Ups the delay giving the IC more time to process the temperature measurement

WiFi.begin(ssid, password);

// Connecting to WiFi network
Serial.println();
Serial.println();
Serial.print("Connecting to ");
Serial.println(ssid);

WiFi.begin(ssid, password);

while (WiFi.status() != WL_CONNECTED) 
{
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected on IP ...");
// Printing the ESP IP address
Serial.println(WiFi.localIP());
}

void getTemperature() {
  float tempC;
  float tempF;
  do {
    DS18B20.requestTemperatures(); 
    tempC = DS18B20.getTempCByIndex(0);
    dtostrf(tempC, 2, 2, temperatureCString);
    tempF = DS18B20.getTempFByIndex(0);
    dtostrf(tempF, 3, 2, temperatureFString);
    delay(100);
  } while (tempC == 85.0 || tempC == (-127.0));
}

// runs over and over again
void loop() 
{

 getTemperature();

if (client.connect(server,80)) {
String postStr = apiKey;
postStr +="&amp;field1=";
postStr += String(temperatureCString);
postStr +="&amp;field2=";
postStr += String(temperatureFString);
postStr += "\r\n\r\n";

client.print("POST /update HTTP/1.1\n");
client.print("Host: api.thingspeak.com\n");
client.print("Connection: close\n");
client.print("X-THINGSPEAKAPIKEY: "+apiKey+"\n");
client.print("Content-Type: application/x-www-form-urlencoded\n");
client.print("Content-Length: ");
client.print(postStr.length());
client.print("\n\n");
client.print(postStr);

Serial.print("Temp in C: ");
Serial.print(temperatureCString);
Serial.print(" and Temp in F: ");
Serial.print(temperatureFString);
Serial.println("Sending data to Thingspeak");
}
client.stop();

Serial.println("Waiting 20 secs");
// thingspeak needs at least a 15 sec delay be een updates
// 20 seconds to be safe
delay(20000);
}
</code></pre>

<p>And this code works fine displaying 2 DS18B20 on serial monitor connected to 1 Onewire BUS, but I need to implement (uncomment) the thingspeak part now.</p>

<pre class="lang-cpp prettyprint-override"><code>#include &lt;ESP8266WiFi.h&gt;
#include &lt;OneWire.h&gt;
#include &lt;DallasTemperature.h&gt;

// replace with your channel’s thingspeak API key and your SSID and password
String apiKey = "THINGSPEAKKEY"; 
const char* ssid = "WIFINAME";
const char* password = "WIFIPASSWORD";
const char* server = "api.thingspeak.com";

/*-----( Declare Constants and Pin Numbers )-----*/
#define ONE_WIRE_BUS_PIN 5

/*-----( Declare objects )-----*/
// Setup a oneWire instance to communicate with any OneWire devices
OneWire oneWire(ONE_WIRE_BUS_PIN);

// Pass our oneWire reference to Dallas Temperature.
DallasTemperature sensors(&amp;oneWire);

DeviceAddress Probe01 = { 0x28, 0xFF, 0x51, 0xA5, 0x61, 0x16, 0x03, 0x92 }; // probe 1
DeviceAddress Probe02 = { 0x28, 0xFF, 0xF8, 0x99, 0x52, 0x16, 0x04, 0xB1 }; // probe 2

WiFiClient client;

void setup()   /****** SETUP: RUNS ONCE ******/
{
  // start serial port to show results
    Serial.begin(115200);
  delay(10);

  // Initialize the Temperature measurement library
  sensors.begin();

 WiFi.begin(ssid, password);

  // Connecting to WiFi network
  Serial.println();
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);

  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED)
  {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.println("WiFi connected on IP ...");
  // Printing the ESP IP address
  Serial.println(WiFi.localIP());

}  //--(end setup )---

/*-----( Declare User-written Functions )-----*/
  void printTemp(DeviceAddress deviceAddress)
  {
  float tempC = sensors.getTempC(deviceAddress);
     if (tempC == -127.00) 
     {
     Serial.print("Error getting temperature  ");
     } 
     else
     {
     Serial.print(tempC);
     }
  }// End printTemp

void loop()   /****** LOOP: RUNS CONSTANTLY ******/
{
  delay(1000);
  Serial.println();
  Serial.print("Number of Devices found on bus = ");  
  Serial.println(sensors.getDeviceCount());   
  Serial.print("Getting temperatures... ");  
  Serial.println();   

  // Command all devices on bus to read temperature  

  sensors.requestTemperatures();  

  Serial.print("Probe 01 temperature is:   ");
    printTemp(Probe01);
  Serial.println();

  Serial.print("Probe 02 temperature is:   ");
    printTemp(Probe02);

  Serial.println();

/*
if (client.connect(server,80)) {
  String postStr = apiKey;
  postStr +="&amp;field1=";
  postStr += float(StrProbe01);
  postStr +="&amp;field2=";
   postStr += float(StrProbe02);
  postStr += "\r\n\r\n";

  client.print("POST /update HTTP/1.1\n");
  client.print("Host: api.thingspeak.com\n");
  client.print("Connection: close\n");
  client.print("X-THINGSPEAKAPIKEY: "+apiKey+"\n");
  client.print("Content-Type: application/x-www-form-urlencoded\n");
  client.print("Content-Length: ");
  client.print(postStr.length());
  client.print("\n\n");
  client.print(postStr);

  Serial.print("Temperature: ");
  Serial.print printTemp(Probe01);
  Serial.print(" degrees Celsius Humidity: ");
  Serial.print printTemp(Probe02);
  Serial.println("Sending data to Thingspeak");
  }
  client.stop();

  Serial.println("Waiting 20 secs");
  // thingspeak needs at least a 15 sec delay be een updates
  // 20 seconds to be safe
  delay(20000);
 */
}//--(end main loop )---
</code></pre>

<p>It has all to do on generate a sort of variable (perhaps float , im not sure) and passing it as a http string</p>

<p>Thanks</p>
 43070: <p>In the code that works, you have:</p>

<pre><code>if (client.connect(server,80)) {
String postStr = apiKey;
postStr +="&amp;field1=";
postStr += String(temperatureCString);
postStr +="&amp;field2=";
postStr += String(temperatureFString);
postStr += "\r\n\r\n";
</code></pre>

<p>In the code that does not work you are doing this:</p>

<pre><code>if (client.connect(server,80)) {
  String postStr = apiKey;
  postStr +="&amp;field1=";
  postStr += float(StrProbe01);
  postStr +="&amp;field2=";
   postStr += float(StrProbe02);
  postStr += "\r\n\r\n";
</code></pre>

<p>Print out the both the Strings that you are sending, postStr, using Serial.print. Compare the result. I'm not at home at the moment to try it out, but I'm sure the float(StrProbe01) and float(StrProbe02) is wrong. Thingspeak explains in their guidelines what the string that you are sending should look like.</p>
