Untested! Soft limits, max travel, homing changes, new settings.

- WARNING: Completely untested. Will later when there is time. Settings
WILL be overwritten, as there are new settings.

- Soft limits installed. Homing must be enabled for soft limits to work
correctly. Errors out much like a hard limit, locking out everything
and bringing up the alarm mode. Only difference is it forces a feed
hold before doing so. Position is not lost.

- IMPORTANT: Homing had to be updated so that soft limits work better
with less CPU overhead. When homing completes, all axes are assumed to
exist in negative space. If your limit switch is other side, the homing
cycle with set this axis location to the max travel value, rather than
zero.

- Update mc_line() to accept an array, rather than individual variables.

- Added an mc_auto_cycle_start() function handle this feature.
Organization only.

-

nuts_bolts.h

@@ -3,7 +3,7 @@
   Part of Grbl
 
   Copyright (c) 2009-2011 Simen Svale Skogsrud
-  Copyright (c) 2011-2012 Sungeun K. Jeon  
+  Copyright (c) 2011-2013 Sungeun K. Jeon  
 
   Grbl is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -32,7 +32,7 @@
 #define true 1
 
 #define N_AXIS 3 // Number of axes
-#define X_AXIS 0 // Axis indexing value
+#define X_AXIS 0 // Axis indexing value. Must start with 0 and be continuous.
 #define Y_AXIS 1
 #define Z_AXIS 2
 
@@ -44,6 +44,7 @@
 // Useful macros
 #define clear_vector(a) memset(a, 0, sizeof(a))
 #define clear_vector_float(a) memset(a, 0.0, sizeof(float)*N_AXIS)
+#define clear_vector_long(a) memset(a, 0.0, sizeof(long)*N_AXIS)
 #define max(a,b) (((a) > (b)) ? (a) : (b))
 #define min(a,b) (((a) < (b)) ? (a) : (b))