Initialize UART and FS

include/defaults.h

@@ -0,0 +1,3 @@
+#pragma once
+
+#define SERIAL_BAUDRATE 115200

src/main.cpp

@@ -1,8 +1,23 @@
+#include "defaults.h"
 #include <Arduino.h>
+#include <LittleFS.h>
 
 void setup()
 {
-    // put your setup code here, to run once:
+    // Initialize serial output
+    Serial.begin(SERIAL_BAUDRATE);
+    while (!Serial)
+        yield();
+    Serial.println();
+    Serial.println(F("Starting OpenDTU"));
+
+    // Initialize file system
+    Serial.print(F("Initialize FS... "));
+    if (!LITTLEFS.begin()) {
+        Serial.println(F("failed"));
+    } else {
+        Serial.println(F("done"));
+    }
 }
 
 void loop()