==사용한 코드==

#include <SoftwareSerial.h>

#include <dht11.h>

#define RX 2

#define TX 3

#define dht_apin 11 // Analog Pin sensor is connected to

dht11 dhtObject;

String AP = "aswin 3F";       // AP NAME

String PASS = "asw1234567"; // AP PASSWORD

String API = "BDT4124TSAZA1S6I";   // Write API KEY

String HOST = "api.thingspeak.com";

String PORT = "80";

int countTrueCommand;

int countTimeCommand;

boolean found = false;

int valSensor = 1;

SoftwareSerial esp8266(RX, TX);

void setup() {

  Serial.begin(9600);

  esp8266.begin(115200);

  sendCommand("AT+CWJAP=\"" + AP + "\",\"" + PASS + "\"", 20, "OK");

}

void loop() {

  String getData = "GET /update?api_key=" + API + "&field1=" + getTemperatureValue() + "&field2=" + getHumidityValue();

  sendCommand("AT+CIPMUX=1", 5, "OK");

  sendCommand("AT+CIPSTART=0,\"TCP\",\"" + HOST + "\"," + PORT, 15, "OK");

  sendCommand("AT+CIPSEND=0," + String(getData.length() + 4), 4, ">");

  esp8266.println(getData); delay(1500); countTrueCommand++;

  sendCommand("AT+CIPCLOSE=0", 5, "OK");

}

String getTemperatureValue() {

  dhtObject.read(dht_apin);

  Serial.print(" Temperature(C)= ");

  int temp = dhtObject.temperature;

  Serial.println(temp);

  delay(50);

  return String(temp);

}

String getHumidityValue() {

  dhtObject.read(dht_apin);

  Serial.print(" Humidity in %= ");

  int humidity = dhtObject.humidity;

  Serial.println(humidity);

  delay(50);

  return String(humidity);

}

void sendCommand(String command, int maxTime, char readReplay[]) {

  Serial.print(countTrueCommand);

  Serial.print(". at command => ");

  Serial.print(command);

  Serial.print(" ");

  while (countTimeCommand < (maxTime * 1))

  {

    esp8266.println(command);//at+cipsend

    if (esp8266.find(readReplay)) //ok

    {

      found = true;

      break;

    }

    countTimeCommand++;

  }

  if (found == true)

  {

    Serial.println("OYI");

    countTrueCommand++;

    countTimeCommand = 0;

  }

  if (found == false)

  {

    Serial.println("Fail");

    countTrueCommand = 0;

    countTimeCommand = 0;

  }

  found = false;

}

(CM1106 코딩값은 라이브러리에서 예제코드 사용) > (시리얼 모니터에 아무것도 뜨지 않는 현상. 정상적이게 업로딩 되었음)