adding arduino examples for DHT11, blink, and temperature sensor

week3/examples/Projects/DHT11_Sensor/src/main.cpp

@@ -0,0 +1,41 @@
+#include <Arduino.h>
+
+#include <DHT.h>
+
+#define DHTPIN 22
+#define DHTTYPE DHT11 //Also can use for DHT22
+
+DHT dht(DHTPIN, DHTTYPE);
+
+
+void setup() {
+  Serial.begin(9600);
+  Serial.println("Initializing sensor");
+  dht.begin();
+}
+
+void loop() {
+  delay(2000);
+  float h = dht.readHumidity();
+  float t = dht.readTemperature();
+  float f = dht.readTemperature(true);
+
+  if (isnan(h)|| isnan(t)|| isnan(f)) {
+    Serial.println(F("Failed to read from sensor"));
+    return;
+  }
+  float hif = dht.computeHeatIndex(f,h);
+  float hic = dht.computeHeatIndex(t,h,false);
+
+  Serial.print(F("Humidity: "));
+  Serial.print(h);
+  Serial.print(F("%   Temperature: "));
+  Serial.print(t);
+  Serial.print(F("deg Cel"));
+  Serial.print(f);
+  Serial.print(F("deg F  Heat index: "));
+  Serial.print(hic);
+  Serial.print(F("deg Celsius "));
+  Serial.print(hif);
+  Serial.println(F("deg F"));
+}