ThingSpeak not showing any data from my ESP32!

It seems like the site isn't receiving any data. The graphics are empty!

Could you please help me? Here's the source code!

Thanks so much!

#ifdef __cplusplus
extern "C" {
#endif
uint8_t temprature_sens_read();
#ifdef __cplusplus
}
#endif
uint8_t temprature_sens_read();
#include <WiFi.h>
String apiKey = "BE7U15RJYY57AV91";                  //  Enter your Write API key from ThingSpeak
const char *ssid =  "Ashish";                                    // replace with your wifi ssid and wpa2 key
const char *pass =  "12345678";
const char* server = "api.thingspeak.com";
WiFiClient client;
void setup() 
{
    Serial.begin(115200);
    delay(10);
    Serial.println("Connecting to ");
    Serial.println(ssid);
    WiFi.begin(ssid, pass);
    while (WiFi.status() != WL_CONNECTED) 
    {
        delay(500);
        Serial.print(".");
    }
    Serial.println("");
    Serial.println("WiFi connected");
 
}
void loop() 
{
  
int h = 0;
float t =0;

h = hallRead();
t = ((temprature_sens_read()-32)/1.8);                //changing temperature parameter to celsius
 if (client.connect(server,80))                                 //   "184.106.153.149" or api.thingspeak.com
    {  
                            
    String postStr = apiKey;
    postStr +="&field1=";
    postStr += String(h);
    postStr += "&field2=";
    postStr += String(t);
    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("Hall: ");
    Serial.println(h);
    Serial.print("Temperature:");
    Serial.print(t);
    Serial.println(" C");
                             
    Serial.println("%. Send to Thingspeak.");
}
    client.stop();
    Serial.println("Waiting...");
    delay(10000);
}

Answer 1

[Vinod]

I strongly recommend using the ThingSpeak library and starting from the examples provided with it.

[Matheus Bitencourt]

Thank you so much.

After using ThingSpeak library, I was able to upload the data!

However, I can't upload more than ONE field for Channel. Can you help me? https://www.mathworks.com/matlabcentral/answers/651273-unable-to-send-data-to-two-fields-at-the-same-channel-can-you-help-me

[Vinod]

Did you try this example?