diff --git a/Grbl_Esp32/system.cpp b/Grbl_Esp32/system.cpp
index e29a9e0f..7785e590 100644
--- a/Grbl_Esp32/system.cpp
+++ b/Grbl_Esp32/system.cpp
@@ -24,16 +24,23 @@
 void system_ini() // Renamed from system_init() due to conflict with esp32 files
 {	
 	// setup control inputs
+#ifdef CONTROL_SAFETY_DOOR_PIN
 	pinMode(CONTROL_SAFETY_DOOR_PIN, INPUT);
-  pinMode(CONTROL_RESET_PIN, INPUT);
-  pinMode(CONTROL_FEED_HOLD_PIN, INPUT);
-  pinMode(CONTROL_CYCLE_START_PIN, INPUT);
+	attachInterrupt(digitalPinToInterrupt(CONTROL_SAFETY_DOOR_PIN), isr_control_inputs, CHANGE);
+#endif
+#ifdef CONTROL_RESET_PIN
+	pinMode(CONTROL_RESET_PIN, INPUT);
+	attachInterrupt(digitalPinToInterrupt(CONTROL_RESET_PIN), isr_control_inputs, CHANGE);
+#endif
+#ifdef CONTROL_FEED_HOLD_PIN
+	pinMode(CONTROL_FEED_HOLD_PIN, INPUT);
+	attachInterrupt(digitalPinToInterrupt(CONTROL_FEED_HOLD_PIN), isr_control_inputs, CHANGE);
+#endif
+#ifdef CONTROL_CYCLE_START_PIN
+	pinMode(CONTROL_CYCLE_START_PIN, INPUT);
+	attachInterrupt(digitalPinToInterrupt(CONTROL_CYCLE_START_PIN), isr_control_inputs, CHANGE);
+#endif
 
-  // attach interrupt to them
-  attachInterrupt(digitalPinToInterrupt(CONTROL_SAFETY_DOOR_PIN), isr_control_inputs, CHANGE);
-  attachInterrupt(digitalPinToInterrupt(CONTROL_RESET_PIN), isr_control_inputs, CHANGE);
-  attachInterrupt(digitalPinToInterrupt(CONTROL_FEED_HOLD_PIN), isr_control_inputs, CHANGE);
-  attachInterrupt(digitalPinToInterrupt(CONTROL_CYCLE_START_PIN), isr_control_inputs, CHANGE); 
 }
 
 void IRAM_ATTR isr_control_inputs()
@@ -421,12 +428,19 @@ uint8_t system_control_get_state()
 	#endif
 	
 	
-  uint8_t control_state = 0;	
+  uint8_t control_state = 0;
+#ifdef CONTROL_SAFETY_DOOR_PIN
   if (digitalRead(CONTROL_SAFETY_DOOR_PIN)) { control_state |= CONTROL_PIN_INDEX_SAFETY_DOOR; } 
+#endif
+#ifdef CONTROL_RESET_PIN
   if (digitalRead(CONTROL_RESET_PIN)) { control_state |= CONTROL_PIN_INDEX_RESET; }
+#endif
+#ifdef CONTROL_FEED_HOLD_PIN
   if (digitalRead(CONTROL_FEED_HOLD_PIN)) { control_state |= CONTROL_PIN_INDEX_FEED_HOLD; }
+#endif
+#ifdef CONTROL_CYCLE_START_PIN
   if (digitalRead(CONTROL_CYCLE_START_PIN)) { control_state |= CONTROL_PIN_INDEX_CYCLE_START; }   
-	
+#endif
   #ifdef INVERT_CONTROL_PIN_MASK
     control_state ^= INVERT_CONTROL_PIN_MASK;
   #endif