diff --git a/ampel-firmware/co2_sensor.cpp b/ampel-firmware/co2_sensor.cpp
index 1ec5e189228e6d13fed275712edbe00d1e628424..32680a200a5cb849b512d90f823d57d7d0f447a7 100644
--- a/ampel-firmware/co2_sensor.cpp
+++ b/ampel-firmware/co2_sensor.cpp
@@ -66,6 +66,7 @@ namespace sensor {
   void setAutoCalibration(int32_t autoCalibration);
 
   void initialize() {
+    Serial.println(F("Sensor   : Senseair S8"));
     S8_serial.begin(S8_BAUDRATE);
     sensor_S8 = new S8_UART(S8_serial);
 #endif
@@ -81,18 +82,14 @@ namespace sensor {
     }
 
     // Show basic S8 sensor info
-    Serial.println(">>> SenseAir S8 NDIR CO2 sensor <<<");
-    printf("Firmware version: %s\n", s8.firm_version);
+    Serial.print(F("S8 - Firmware : "));
+    Serial.println(s8.firm_version);
     s8.sensor_id = sensor_S8->get_sensor_ID();
-    Serial.print("Sensor ID: 0x");
+    Serial.print("S8 - ID : 0x");
     printIntToHex(s8.sensor_id, 4);
     Serial.println("");
 
-    Serial.println("Setup done!");
-    Serial.flush();
-
-    Serial.print(F("Auto-calibration is "));
-    Serial.println(config::auto_calibrate_sensor ? "ON." : "OFF.");
+    //TODO: Auto-calibration on/off?
 
     // S8 has its own timer (constant 4s)
     Serial.println();
@@ -102,7 +99,7 @@ namespace sensor {
     check_timestep = config::measurement_timestep_bootup;
 
     sensor_console::defineIntCommand("co2", setCO2forDebugging, F("1500 (Sets co2 level, for debugging)"));
-//    sensor_console::defineIntCommand("timer", setTimer, F("30 (Sets measurement interval, in s)"));
+    sensor_console::defineIntCommand("timer", setTimer, F("30 (Sets measurement interval, in s)"));
 //    sensor_console::defineCommand("calibrate", startCalibrationProcess, F("(Starts calibration process)"));
 //    sensor_console::defineIntCommand("calibrate", calibrateSensorToSpecificPPM,
 //        F("600 (Starts calibration process, to given ppm)"));
@@ -152,10 +149,7 @@ namespace sensor {
     Serial.print(timestamp);
     Serial.print(F(" - co2(ppm): "));
     Serial.print(co2);
-    Serial.print(F(" temp(C): "));
-    Serial.print(temperature, 1);
-    Serial.print(F(" humidity(%): "));
-    Serial.println(humidity, 1);
+    Serial.println(F(" temp(C): ? humidity(%): ?"));
   }
 
   void switchState(state new_state) {
@@ -246,6 +240,7 @@ namespace sensor {
       last_measurement = now;
       ntp::getLocalTime(timestamp);
       co2 = sensor_S8->get_co2();
+      //TODO: Check if there's really no temperature info available.
       temperature = 0.0;
       humidity = 0.0;
 
@@ -277,34 +272,29 @@ namespace sensor {
   }
 
   void setAutoCalibration(int32_t autoCalibration) {
-    Serial.println(F("Implement ME!"));
+    Serial.println(F("TODO: Implement ME!"));
   }
 
   void setTimer(int32_t timestep) {
-    Serial.println(F("Implement ME!"));
+    if (timestep >= 4) {
+      Serial.print(F("Setting Measurement Interval to : "));
+      Serial.print(timestep);
+      Serial.println(F("s."));
+      check_timestep = timestep;
+      config::measurement_timestep = timestep;
+      led_effects::showKITTWheel(color::green, 1);
+    }
   }
 
   void calibrateSensorToSpecificPPM(int32_t calibrationLevel) {
-    if (calibrationLevel >= 400 && calibrationLevel <= 2000) {
-      Serial.print(F("Force calibration, at "));
-      config::co2_calibration_level = calibrationLevel;
-      Serial.print(config::co2_calibration_level);
-      Serial.println(F(" ppm."));
-      startCalibrationProcess();
-    }
+    Serial.println(F("TODO: Implement ME!"));
   }
 
   void calibrateSensorRightNow(int32_t calibrationLevel) {
-    if (calibrationLevel >= 400 && calibrationLevel <= 2000) {
-      Serial.print(F("Force calibration, right now, at "));
-      config::co2_calibration_level = calibrationLevel;
-      Serial.print(config::co2_calibration_level);
-      Serial.println(F(" ppm."));
-      calibrate();
-    }
+    Serial.println(F("TODO: Implement ME!"));
   }
 
   void resetSCD() {
-    Serial.println(F("Implement ME!"));
+    Serial.println(F("TODO: Implement ME! (or delete me)"));
   }
 }