adding arduino examples for DHT11, blink, and temperature sensor

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

@@ -0,0 +1,77 @@
+#include <Arduino.h>
+
+// Include the libraries we need
+#include <OneWire.h>
+#include <DallasTemperature.h>
+
+// Data wire is plugged into port 2 on the Pico
+#define ONE_WIRE_BUS 17
+
+// External timer pin
+const int inputPin = 21;
+
+// 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 sensors(&oneWire);
+
+/*
+ * The setup function. We only start the sensors here
+ */
+void setup(void)
+{
+  pinMode(LED_BUILTIN, OUTPUT);
+  // start serial port
+  Serial.begin(9600);
+  Serial.println("Dallas Temperature IC Control Library Demo");
+
+  // Start up the library
+  sensors.begin();
+
+  // Configure the timing pin as an input with an internal pull-down resistor.
+  // This ensures the pin reads LOW when no signal is present.
+  pinMode(inputPin, INPUT_PULLDOWN);
+}
+
+/*
+ * Main function, get and show the temperature
+ */
+void loop(void)
+{
+  // Read the state of the pin
+  int sensorValue = digitalRead(inputPin);
+
+  // Check if the pin is HIGH
+  if (sensorValue == HIGH) {
+    Serial.println("GPIO 21 is HIGH");
+    // Add your HIGH-state logic here
+  } else {
+    Serial.println("GPIO 21 is LOW");
+  }
+
+  // Small delay to prevent flooding the serial monitor
+  delay(100);
+
+  // call sensors.requestTemperatures() to issue a global temperature
+  // request to all devices on the bus
+  Serial.print("Requesting temperatures...");
+  sensors.requestTemperatures(); // Send the command to get temperatures
+  Serial.println("DONE");
+  digitalWrite(LED_BUILTIN, HIGH);   // turn the LED on (HIGH is the voltage level)
+  delay(1500);
+  digitalWrite(LED_BUILTIN, LOW);   // turn the LED off (HIGH is the voltage level)
+  // After we got the temperatures, we can print them here.
+  // We use the function ByIndex, and as an example get the temperature from the first sensor only.
+  float tempC = sensors.getTempCByIndex(0);
+  // Check if reading was successful
+  if (tempC != DEVICE_DISCONNECTED_C)
+  {
+    Serial.print("Temperature for the device 1 (index 0) is: ");
+    Serial.println(tempC);
+  }
+  else
+  {
+    Serial.println("Error: Could not read temperature data");
+  }
+}