Minor updates to line number feature.

- Changed line number integer types from unsigned to signed int32.
G-code mandates values cannot exceed 99999. Negative values can be used
to indicate certain modes.

- Homing cycle line number changed to -1, as an indicator.

- Fixed a reporting define for the spindle states that was broken by
the last merge.

config.h

@@ -28,10 +28,6 @@
 #ifndef config_h
 #define config_h
 
-// Allows GRBL to tranck and report gcode line numbers.  Enabling this means that the planning buffer
-// goes from 18 or 16 to make room for the additional line number data in the plan_block_t struct
-#define USE_LINE_NUMBERS
-
 // Default settings. Used when resetting EEPROM. Change to desired name in defaults.h
 #define DEFAULTS_SHERLINE_5400
 
@@ -88,6 +84,10 @@
 // parser state depending on user preferences.
 #define N_STARTUP_LINE 2 // Integer (1-3)
 
+// Allows GRBL to tranck and report gcode line numbers.  Enabling this means that the planning buffer
+// goes from 18 or 16 to make room for the additional line number data in the plan_block_t struct
+// #define USE_LINE_NUMBERS
+
 // Enables a second coolant control pin via the mist coolant g-code command M7 on the Arduino Uno
 // analog pin 5. Only use this option if you require a second coolant control pin.
 // NOTE: The M8 flood coolant control pin on analog pin 4 will still be functional regardless.

gcode.c

@@ -101,7 +101,7 @@ uint8_t gc_execute_line(char *line)
   float target[N_AXIS];
   clear_vector(target); // XYZ(ABC) axes parameters.
 
-  uint32_t line_number = 0;
+  int32_t line_number = 0;
   gc.arc_radius = 0;
   clear_vector(gc.arc_offset); // IJK Arc offsets are incremental. Value of zero indicates no change.
 

motion_control.c

@@ -39,7 +39,7 @@
 // segments, must pass through this routine before being passed to the planner. The seperation of
 // mc_line and plan_buffer_line is done primarily to place non-planner-type functions from being
 // in the planner and to let backlash compensation or canned cycle integration simple and direct.
-void mc_line(float *target, float feed_rate, uint8_t invert_feed_rate, uint32_t line_number)
+void mc_line(float *target, float feed_rate, uint8_t invert_feed_rate, int32_t line_number)
 {
   // If enabled, check for soft limit violations. Placed here all line motions are picked up
   // from everywhere in Grbl.
@@ -87,7 +87,7 @@ void mc_line(float *target, float feed_rate, uint8_t invert_feed_rate, uint32_t
 // of each segment is configured in settings.arc_tolerance, which is defined to be the maximum normal
 // distance from segment to the circle when the end points both lie on the circle.
 void mc_arc(float *position, float *target, float *offset, uint8_t axis_0, uint8_t axis_1, 
-  uint8_t axis_linear, float feed_rate, uint8_t invert_feed_rate, float radius, uint8_t isclockwise, uint32_t line_number)
+  uint8_t axis_linear, float feed_rate, uint8_t invert_feed_rate, float radius, uint8_t isclockwise, int32_t line_number)
 {      
   float center_axis0 = position[axis_0] + offset[axis_0];
   float center_axis1 = position[axis_1] + offset[axis_1];

motion_control.h

@@ -22,19 +22,20 @@
 #ifndef motion_control_h
 #define motion_control_h
 
-#define HOMING_CYCLE_LINE_NUMBER 1000000000
+#define HOMING_CYCLE_LINE_NUMBER -1
+
 
 // Execute linear motion in absolute millimeter coordinates. Feed rate given in millimeters/second
 // unless invert_feed_rate is true. Then the feed_rate means that the motion should be completed in
 // (1 minute)/feed_rate time.
-void mc_line(float *target, float feed_rate, uint8_t invert_feed_rate, uint32_t line_number);
+void mc_line(float *target, float feed_rate, uint8_t invert_feed_rate, int32_t line_number);
 
 // Execute an arc in offset mode format. position == current xyz, target == target xyz, 
 // offset == offset from current xyz, axis_XXX defines circle plane in tool space, axis_linear is
 // the direction of helical travel, radius == circle radius, isclockwise boolean. Used
 // for vector transformation direction.
 void mc_arc(float *position, float *target, float *offset, uint8_t axis_0, uint8_t axis_1,
-  uint8_t axis_linear, float feed_rate, uint8_t invert_feed_rate, float radius, uint8_t isclockwise, uint32_t line_number);
+  uint8_t axis_linear, float feed_rate, uint8_t invert_feed_rate, float radius, uint8_t isclockwise, int32_t line_number);
   
 // Dwell for a specific number of seconds
 void mc_dwell(float seconds);

planner.c

@@ -259,7 +259,7 @@ uint8_t plan_check_full_buffer()
    is used in three ways: as a normal feed rate if invert_feed_rate is false, as inverse time if
    invert_feed_rate is true, or as seek/rapids rate if the feed_rate value is negative (and
    invert_feed_rate always false). */
-void plan_buffer_line(float *target, float feed_rate, uint8_t invert_feed_rate, uint32_t line_number) 
+void plan_buffer_line(float *target, float feed_rate, uint8_t invert_feed_rate, int32_t line_number) 
 {
   // Prepare and initialize new block
   plan_block_t *block = &block_buffer[block_buffer_head];
@@ -267,9 +267,10 @@ void plan_buffer_line(float *target, float feed_rate, uint8_t invert_feed_rate,
   block->millimeters = 0;
   block->direction_bits = 0;
   block->acceleration = SOME_LARGE_VALUE; // Scaled down to maximum acceleration later
-#ifdef USE_LINE_NUMBERS
+  #ifdef USE_LINE_NUMBERS
     block->line_number = line_number;
-#endif
+  #endif
+
   // Compute and store initial move distance data.
   // TODO: After this for-loop, we don't touch the stepper algorithm data. Might be a good idea
   // to try to keep these types of things completely separate from the planner for portability.

planner.h

@@ -51,9 +51,10 @@ typedef struct {
   float acceleration;            // Axis-limit adjusted line acceleration in (mm/min^2)
   float millimeters;             // The remaining distance for this block to be executed in (mm)
   // uint8_t max_override;       // Maximum override value based on axis speed limits
-#ifdef USE_LINE_NUMBERS
-  uint32_t line_number;
-#endif
+
+  #ifdef USE_LINE_NUMBERS
+    int32_t line_number;
+  #endif
 } plan_block_t;
 
       
@@ -63,7 +64,7 @@ void plan_reset();
 // Add a new linear movement to the buffer. target[N_AXIS] is the signed, absolute target position 
 // in millimeters. Feed rate specifies the speed of the motion. If feed rate is inverted, the feed
 // rate is taken to mean "frequency" and would complete the operation in 1/feed_rate minutes.
-void plan_buffer_line(float *target, float feed_rate, uint8_t invert_feed_rate, uint32_t line_number);
+void plan_buffer_line(float *target, float feed_rate, uint8_t invert_feed_rate, int32_t line_number);
 
 // Called when the current block is no longer needed. Discards the block and makes the memory
 // availible for new blocks.

report.c

@@ -262,9 +262,9 @@ void report_gcode_modes()
   }
 
   switch (gc.spindle_direction) {
-    case 1 : printPgmString(PSTR(" M3")); break;
-    case -1 : printPgmString(PSTR(" M4")); break;
-    case 0 : printPgmString(PSTR(" M5")); break;
+    case SPINDLE_ENABLE_CW : printPgmString(PSTR(" M3")); break;
+    case SPINDLE_ENABLE_CCW : printPgmString(PSTR(" M4")); break;
+    case SPINDLE_DISABLE : printPgmString(PSTR(" M5")); break;
   }
   
   switch (gc.coolant_mode) {
@@ -353,9 +353,8 @@ void report_realtime_status()
     
 #ifdef USE_LINE_NUMBERS
   // Report current line number
-  printPgmString(PSTR(","));
-  printPgmString(PSTR("Ln:")); 
-  uint32_t ln=0;
+  printPgmString(PSTR(",Ln:")); 
+  int32_t ln=0;
   plan_block_t * pb = plan_get_current_block();
   if(pb != NULL) {
     ln = pb->line_number;