Merge pull request MarlinFirmware#251 from ZetaPhoenix/Marlin_v1_bugfix

Limit Switch locations based on MIN/MAX limits and homing direction

Marlin/Configuration.h

@@ -203,10 +203,14 @@ const bool Z_ENDSTOPS_INVERTING = true; // set to true to invert the logic of th
 #define Y_MAX_LENGTH (Y_MAX_POS - Y_MIN_POS)
 #define Z_MAX_LENGTH (Z_MAX_POS - Z_MIN_POS)
 
-// The position of the homing switches. Use MAX_LENGTH * -0.5 if the center should be 0, 0, 0
-#define X_HOME_POS 0
-#define Y_HOME_POS 0
-#define Z_HOME_POS 0
+// The position of the homing switches
+//#define MANUAL_HOME_POSITIONS  // If defined, manualy programed locations will be used
+//#define BED_CENTER_AT_0_0  // If defined the center of the bed is defined as (0,0)
+
+//Manual homing switch locations:
+#define MANUAL_X_HOME_POS 0
+#define MANUAL_Y_HOME_POS 0
+#define MANUAL_Z_HOME_POS 0
 
 //// MOVEMENT SETTINGS
 #define NUM_AXIS 4 // The axis order in all axis related arrays is X, Y, Z, E

Marlin/Configuration_adv.h

@@ -76,6 +76,54 @@
 
 #define ENDSTOPS_ONLY_FOR_HOMING // If defined the endstops will only be used for homing
 
+
+//// AUTOSET LOCATIONS OF LIMIT SWITCHES
+//// Added by ZetaPhoenix 09-15-2012
+#ifdef MANUAL_HOME_POSITION  //Use manual limit switch locations
+  #define X_HOME_POS MANUAL_X_HOME_POS
+  #define Y_HOME_POS MANUAL_Y_HOME_POS
+  #define Z_HOME_POS MANUAL_Z_HOME_POS
+#else //Set min/max homing switch positions based upon homing direction and min/max travel limits
+  //X axis
+  #if X_HOME_DIR == -1
+    #ifdef BED_CENTER_AT_0_0
+      #define X_HOME_POS X_MAX_LENGTH * -0.5
+    #else
+      #define X_HOME_POS X_MIN_POS
+    #endif //BED_CENTER_AT_0_0
+  #else    
+    #ifdef BED_CENTER_AT_0_0
+      #define X_HOME_POS X_MAX_LENGTH * 0.5
+    #else
+      #define X_HOME_POS X_MAX_POS
+    #endif //BED_CENTER_AT_0_0
+  #endif //X_HOME_DIR == -1
+
+  //Y axis
+  #if Y_HOME_DIR == -1
+    #ifdef BED_CENTER_AT_0_0
+      #define Y_HOME_POS Y_MAX_LENGTH * -0.5
+    #else
+      #define Y_HOME_POS Y_MIN_POS
+    #endif //BED_CENTER_AT_0_0
+  #else    
+    #ifdef BED_CENTER_AT_0_0
+      #define Y_HOME_POS Y_MAX_LENGTH * 0.5
+    #else
+      #define Y_HOME_POS Y_MAX_POS
+    #endif //BED_CENTER_AT_0_0
+  #endif //Y_HOME_DIR == -1
+
+  // Z axis
+  #if Z_HOME_DIR == -1 //BED_CENTER_AT_0_0 not used
+    #define Z_HOME_POS Z_MIN_POS
+  #else    
+    #define Z_HOME_POS Z_MAX_POS
+  #endif //Z_HOME_DIR == -1
+#endif //End auto min/max positions
+//END AUTOSET LOCATIONS OF LIMIT SWITCHES -ZP
+
+
 //#define Z_LATE_ENABLE // Enable Z the last moment. Needed if your Z driver overheats.
 
 // A single Z stepper driver is usually used to drive 2 stepper motors.