diff --git a/lambda/Makefile b/lambda/Makefile
index 5525397..8da700c 100644
--- a/lambda/Makefile
+++ b/lambda/Makefile
@@ -3,7 +3,7 @@
 
 MCU = atmega328p
 # Currently supported are 1 MHz and 8 MHz
-F_CPU = 8000000
+F_CPU = 1000000
 # Also try BAUD = 19200 or 38400 if you're feeling lucky.
 BAUD = 9600
 
diff --git a/lambda/airgate.c b/lambda/airgate.c
index 9d7cab6..e60c5ce 100644
--- a/lambda/airgate.c
+++ b/lambda/airgate.c
@@ -21,8 +21,7 @@
 #include "airgate.h"
 #include "integers.h"
 #include "interrupts.h"
-
-// TODO pins
+#include "pins.h"
 
 /* Direction */
 volatile static int8_t dir = 0;
@@ -44,17 +43,17 @@
  * starts the motor by starting the timer.
  */
 static void start(void) {
-	if (bit_is_clear(PORTC, PC5)) {
+	if (bit_is_clear(PORT, PIN_SLEEP)) {
 		// wake up driver
-		PORTC |= (1 << PC5);
+		PORT |= (1 << PIN_SLEEP);
 		// wakeup time
 		_delay_ms(2);
 	}
 	// set dir
 	if (dir == 1) {
-		PORTB &= ~(1 << PB6);
+		PORT &= ~(1 << PIN_DIR);
 	} else {
-		PORTB |= (1 << PB6);
+		PORT |= (1 << PIN_DIR);
 	}
 	// setup time
 	_delay_us(1);
@@ -79,19 +78,20 @@
  * the motor.
  */
 static void set(void) {
-	stop();
 	int16_t diff = (((int16_t)target) << SCALE) - pos;
 	if (diff != 0) {
 		dir = MAX(-1, MIN(diff, 1));
 		steps = abs(diff);
 		ramp = MIN(abs(MAX_SPEED - MIN_SPEED), steps >> 1);
 		start();
+	} else {
+		setSleepMode();
 	}
 }
 
 void makeSteps(void) {
 	if (steps > 0) {
-		PORTB ^= (1 << PB7);
+		PORT ^= (1 << PIN_STEP);
 		done++;
 		steps--;
 		if (done < ramp && speed < MAX_SPEED) {
@@ -104,6 +104,7 @@
 		// linearize an unfavourably increasing acceleration curve
 		OCR2A = (MIN_SPEED * MAX_SPEED) / speed;
 	} else {
+		stop();
 		pos += (done * dir);
 		done = 0;
 		// move to new target position if necessary
@@ -135,5 +136,5 @@
 }
 
 void setSleepMode(void) {
-	PORTC &= ~(1 << PC5);
+	PORT &= ~(1 << PIN_SLEEP);
 }
diff --git a/lambda/display.c b/lambda/display.c
index c782d54..08eb461 100644
--- a/lambda/display.c
+++ b/lambda/display.c
@@ -22,6 +22,7 @@
 #include "alert.h"
 #include "messages.h"
 #include "rules.h"
+#include "airgate.h"
 
 DisplayPos position = displayPosCurrent;
 bool updatePending = false;
@@ -79,6 +80,15 @@
 }
 
 /**
+ * Displays the airgate position in %.
+ */
+static void displayAirgate(uint8_t const airgate) {
+	char line1[17];
+	snprintf(line1, sizeof(line1), "%d%%", airgate);
+	setText(MSG_AIRGATE, line1);
+}
+
+/**
  * Formats and displays the time since last start/reset.
  */
 static void displayTime(void) {
@@ -126,10 +136,12 @@
 
 		if (position == displayPosMax) {
 			displayMeas(measMax, " ^");
-		} else if (position == displayPosLastText) {
-			setText(lastLine0, lastLine1);
+		} else if (position == displayPosAirgate) {
+			displayAirgate(getAirgate());
 		} else if (position == displayPosHeater) {
 			displayCurrent(measLatest.current);
+		} else if (position == displayPosLastText) {
+			setText(lastLine0, lastLine1);
 		} else if (position == displayPosTime) {
 			displayTime();
 		} else {
diff --git a/lambda/display.h b/lambda/display.h
index 4a51fb0..0b46583 100644
--- a/lambda/display.h
+++ b/lambda/display.h
@@ -19,9 +19,10 @@
 typedef enum {
 	displayPosCurrent = 0,
 	displayPosMax = 1,
-	displayPosHeater = 2,
-	displayPosLastText = 3,
-	displayPosTime = 4
+	displayPosAirgate = 2,
+	displayPosHeater = 3,
+	displayPosLastText = 4,
+	displayPosTime = 5
 } DisplayPos;
 
 uint8_t getPosition(void);
diff --git a/lambda/interrupts.c b/lambda/interrupts.c
index ae5c439..ebdf46a 100644
--- a/lambda/interrupts.c
+++ b/lambda/interrupts.c
@@ -86,11 +86,9 @@
 	DDR |= (1 << PIN_HEATER);
 
 	// enable dir and step pin for stepper motor driver
-	// TODO pins
-	DDR |= (1 << PB6);
-	DDR |= (1 << PB7);
-	// DDR |= (1 << PB3); // (OC2A)
-	DDRC |= (1 << PC5);
+	DDR |= (1 << PIN_SLEEP);
+	DDR |= (1 << PIN_STEP);
+	DDR |= (1 << PIN_DIR);
 }
 
 void setupSleepMode(void) {
diff --git a/lambda/messages.h b/lambda/messages.h
index 20f1e27..33011af 100644
--- a/lambda/messages.h
+++ b/lambda/messages.h
@@ -23,6 +23,9 @@
 	#define MSG_IDEAL "Ideal"
 	#define MSG_RICH "Rich!"
 
+	/* display.c */
+	#define MSG_AIRGATE "Air gate"
+
 	/* rules.c */
 	#define MSG_AIRGATE_50_0 "Air gate 50%"
 	#define MSG_AIRGATE_25_0 "Air gate 25%"
@@ -50,6 +53,9 @@
 	#define MSG_IDEAL "Ideal"
 	#define MSG_RICH "Fett!"
 
+	/* display.c */
+	#define MSG_AIRGATE "Luftschieber"
+
 	/* rules.c */
 	#define MSG_AIRGATE_50_0 "Luftschieber 50%"
 	#define MSG_AIRGATE_25_0 "Luftschieber 25%"
diff --git a/lambda/pins.h b/lambda/pins.h
index 244c81d..4374476 100644
--- a/lambda/pins.h
+++ b/lambda/pins.h
@@ -35,6 +35,12 @@
 #define PIN_BEEPER_TOGGLE COM1A0
 /** Pin for the oxygen sensor heater */
 #define PIN_HEATER PB2
+/** Pin for the stepper motor driver sleep mode **/
+#define PIN_SLEEP PB3
+/** Pin for the stepper motor driver step input */
+#define PIN_STEP PB4
+/** Pin for the stepper motor driver direction input */
+#define PIN_DIR PB5
 
 /* Pins for the LCD */
 #define LCD_PORT PORTD