Config default changes

- Changed acceleration defaults to more sane values.
- Enabled LINEAR Autoleveling (for testing stuff. If you use a real
sensor you need to specify the offset and should enable Z_SAFE_HOMING!)

Marlin/Configuration.h

@@ -493,7 +493,7 @@
  * Override with M92
  *                                      X, Y, Z, E0 [, E1[, E2[, E3]]]
  */
-#define DEFAULT_AXIS_STEPS_PER_UNIT   {100,  100, 400,90}
+#define DEFAULT_AXIS_STEPS_PER_UNIT   {100,  100, 400, 95}
 
 /**
  * Default Max Feed Rate (mm/s)
@@ -508,7 +508,7 @@
  * Override with M201
  *                                      X, Y, Z, E0 [, E1[, E2[, E3]]]
  */
-#define DEFAULT_MAX_ACCELERATION      {3000,3000,1000,5000}
+#define DEFAULT_MAX_ACCELERATION      { 1000, 1000, 100, 5000 }
 /**
  * Default Acceleration (change/s) change = mm/s
  * Override with M204
@@ -517,9 +517,9 @@
  *   M204 R    Retract Acceleration
  *   M204 T    Travel Acceleration
  */
-#define DEFAULT_ACCELERATION          1000    // X, Y, Z and E acceleration for printing moves
-#define DEFAULT_RETRACT_ACCELERATION  3000    // E acceleration for retracts
-#define DEFAULT_TRAVEL_ACCELERATION   3000    // X, Y, Z acceleration for travel (non printing) moves
+#define DEFAULT_ACCELERATION          400     // X, Y, Z and E acceleration for printing moves
+#define DEFAULT_RETRACT_ACCELERATION  1000    // E acceleration for retracts
+#define DEFAULT_TRAVEL_ACCELERATION   400    // X, Y, Z acceleration for travel (non printing) moves
 
 /**
  * Default Jerk (mm/s)
@@ -531,7 +531,7 @@
  */
 #define DEFAULT_XJERK                 20.0
 #define DEFAULT_YJERK                 20.0
-#define DEFAULT_ZJERK                  0.4
+#define DEFAULT_ZJERK                  0.3
 #define DEFAULT_EJERK                  5.0
 
 
@@ -640,7 +640,7 @@
 
 /////////////////////////////////////////////////////////////////////////////////////////////////
 // X and Y axis travel speed (mm/m) between probes
-#define XY_PROBE_SPEED 8000
+#define XY_PROBE_SPEED 6000
 
 // Speed for the first approach when double-probing (with PROBE_DOUBLE_TOUCH)
 #define Z_PROBE_SPEED_FAST HOMING_FEEDRATE_Z
@@ -859,7 +859,7 @@
  *   With an LCD controller the process is guided step-by-step.
  */
 //#define AUTO_BED_LEVELING_3POINT
-//#define AUTO_BED_LEVELING_LINEAR
+#define AUTO_BED_LEVELING_LINEAR
 //#define AUTO_BED_LEVELING_BILINEAR
 //#define AUTO_BED_LEVELING_UBL
 //#define MESH_BED_LEVELING
@@ -997,8 +997,8 @@
 #endif
 
 // Homing speeds (mm/m)
-#define HOMING_FEEDRATE_XY (50*60)
-#define HOMING_FEEDRATE_Z  (6*60)
+#define HOMING_FEEDRATE_XY (100*60)
+#define HOMING_FEEDRATE_Z  (4*60)
 
 //=============================================================================
 //============================= Additional Features ===========================