commit 18038ecdb9a9a82c0f5fb610faa2d7a7acf47767
Author: Sebastian Hernø Gabrielli (Elev) <sebastiang@viken.no>
Date:   Mon Apr 19 10:54:48 2021 +0200

    Initial commit

diff --git a/ESP-MQTT-client-temp.ino b/ESP-MQTT-client-temp.ino
new file mode 100644
index 0000000..96b1729
--- /dev/null
+++ b/ESP-MQTT-client-temp.ino
@@ -0,0 +1,116 @@
+#include <WiFi.h>
+#include <PubSubClient.h>
+#include <Wire.h>
+
+#define O_LED 2
+int PIN_ANALOG_IN = 39;
+
+const char* ssid = "BFKBYOD";
+const char* password = "bfkskoleelev";
+const char* mqtt_broker = "109.74.205.66";
+int mqtt_port = 443;
+
+WiFiClient espClient;
+
+PubSubClient mqtt_client(espClient);
+
+String lastMsg;
+
+#define MSG_BUFFER_SIZE (50)
+char msg[MSG_BUFFER_SIZE];
+
+void setup_wifi() {
+  delay(10);
+
+  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");
+  Serial.print("IP address: ");
+  Serial.println(WiFi.localIP());
+}
+
+void callback(char* topic, byte* payload, unsigned int length) {
+  Serial.print("Message arrived [");
+  Serial.print(topic);
+  Serial.print("] ");
+
+  lastMsg = "";
+
+  for (int i = 0; i < length; i++) {
+    Serial.print((char)payload[i]);
+    lastMsg += (char)payload[i];
+  }
+  Serial.println();
+  
+  if ((String)topic == "sebastian/control" && lastMsg == "on") {
+    digitalWrite(O_LED, HIGH);
+  } else if ((String)topic == "sebastian/control" && lastMsg == "off") {
+    digitalWrite(O_LED, LOW);
+  }
+}
+
+void reconnect () {
+  while (!mqtt_client.connected()) {
+    Serial.print("Attempting MQTT connection...");
+
+    String clientId = "ESP32Client-";
+    clientId += String(random(0xffff), HEX);
+
+    if (mqtt_client.connect(clientId.c_str())) {
+      Serial.println("connected");
+
+      mqtt_client.publish("ClientAnnouncements", "Sebastian");
+
+      mqtt_client.subscribe("inTopic");
+      mqtt_client.subscribe("sebastian/control");
+    } else {
+      Serial.print("failed, rc=");
+      Serial.print(mqtt_client.state());
+      Serial.println(" trying again in 5 seconds");
+      delay(5000);
+    }
+  }
+}
+
+void setup() {
+   pinMode(O_LED, OUTPUT);
+
+   Serial.begin(9600);
+
+   setup_wifi();
+
+   mqtt_client.setServer(mqtt_broker, mqtt_port);
+   mqtt_client.setCallback(callback);
+}
+
+void loop() {
+  if (!mqtt_client.connected()) {
+    reconnect();
+  }
+
+  int adcValue = analogRead(PIN_ANALOG_IN);                       //read ADC pin
+  double voltage = (float)adcValue / 4095.0 * 3.3;                // calculate voltage
+  double Rt = 10 * voltage / (3.3 - voltage);                     //calculate resistance value of thermistor
+  double tempK = 1 / (1 / (273.15 + 25) + log(Rt / 10) / 3950.0); //calculate temperature (Kelvin)
+  double tempC = tempK - 273.15;                                  //calculate temperature (Celsius)
+  //Serial.printf("ADC value : %d,\tVoltage : %.2fV, \tTemperature : %.2fC\n", adcValue, voltage, tempC);
+
+  char CharArrTemp[6];
+  dtostrf(tempC, 5, 2, CharArrTemp);
+
+  mqtt_client.publish("sebastian/temp", CharArrTemp);
+
+  delay(500);
+
+  mqtt_client.loop();
+}
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..1d39011
--- /dev/null
+++ b/README.md
@@ -0,0 +1,2 @@
+#ESP MQTT Client Temperature
+This is example code for sending temperature data to a MQTT broker