LED switch exercise

arduino/LEDSwitch/LEDSwitch.ino

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+const unsigned int LED_PIN = 13;
+const unsigned int BAUD_RATE = 9600;
+
+void setup() {
+  pinMode(LED_PIN, OUTPUT);
+  Serial.begin(BAUD_RATE);
+}
+
+void loop() {
+  if (Serial.available() <= 0) {
+    return;
+  }
+
+  int command = Serial.read();
+
+  switch (command) {
+  case '1':
+    digitalWrite(LED_PIN, HIGH);
+    Serial.println("LED on");
+    break;
+  case '2':
+    digitalWrite(LED_PIN, LOW);
+    Serial.println("LED off");
+    break;
+  default:
+    Serial.print("Unknown command: ");
+    Serial.println(command);
+  }
+}

arduino/LEDSwitch/Makefile

@@ -0,0 +1 @@
+../arduino.mk