v1.1d: Tweaked interface a bit. Added realtime spindle speed and build option data. Minor bug fixes.

- Increment to v1.1d due to interface tweaks.

- Based on GUI dev feedback, the toggle overrides report was removed
and replace with showing “accessory state”. This shows a character if a
particular accessory is enabled, like the spindle or flood coolant.
These can be directly altered by the toggle overrides, so when they
execute, a GUI will be able to observe the state altering as feedback.

- Altered the real-time feed rate to show real-time spindle speed as
well. It was an over-sight on my part. It’s needed because it’s hard to
know what the current spindle speed is when overrides are altering it.
Especially during something like a laser cutting job when its important
to know how spindle speed overrides are effecting things.

- Real-time spindle speed is not shown if VARIABLE_SPINDLE is disabled.
The old real-time feed rate data field will show instead.

- Compile-time option data is now included in another message
immediately following the build info version string, starting with
`[OPT:`. A character code follows the data type name with each
indicating a particular option enabled or disabled. This will help
immensely with debugging Grbl as well as help GUIs know exactly how
Grbl was compiled.

- These interface changes are detailed in the updated documentation.

- Reduced the default planner buffer size from 17 to 16. Needed to free
up some memory…

- For increasing the serial TX buffer size from 90 to 104 bytes. The
addition of real-time spindle speeds and accessory enable data required
a bigger buffer. This is to ensure Grbl is performing at optimal levels.

- Refactored parts of the spindle and coolant control code to make it
more consistent to each other and how it was called. It was a little
messy. The changes made it easier to track what each function call was
doing based on what was calling it.

- Created a couple of new get_state functions for the spindle and
coolant. These are called by the accessory state report to look
directly at the pin state, rather than track how it was set. This
guarantees that the state is reported correctly.

- Updated the g-code parser, parking motion, sleep mode, and spindle
stop calls to refactored spindle and coolant code.

- Added a compile-time option to enable homing individual axes, rather
than having only the main homing cycle. The actual use case for this is
pretty rare. It’s not recommended you enable this, unless you have a
specific application for it. Otherwise, just alter the homing cycle
itself.

- Refactored the printFloat() function to not show a decimal point if
there are no trailing values after it. For example, `1.` now shows `1`.

- Fixed an issue regarding spindle speed overrides no being applied to
blocks without motions.

- Removed the toggle_ovr_mask system variable and replaced with
spindle_stop_ovr system variable. Coolant toggles don’t need to be
tracked.

- Updated README

grbl/system.h

@@ -114,15 +114,12 @@
   #define CONTROL_PIN_INDEX_CYCLE_START   bit(2)
 #endif
 
-// Define toggle override control states.
-#define TOGGLE_OVR_STOP_ENABLED        bit(0)
-#define TOGGLE_OVR_STOP_INITIATE       bit(1)
-#define TOGGLE_OVR_STOP_RESTORE        bit(2)
-#define TOGGLE_OVR_STOP_RESTORE_CYCLE  bit(3)
-#define TOGGLE_OVR_FLOOD_COOLANT       bit(4)
-#define TOGGLE_OVR_MIST_COOLANT        bit(5)
-#define TOGGLE_OVR_STOP_ACTIVE_MASK  (TOGGLE_OVR_STOP_ENABLED|TOGGLE_OVR_STOP_INITIATE|TOGGLE_OVR_STOP_RESTORE|TOGGLE_OVR_STOP_RESTORE_CYCLE)
-// NOTE: Mask is used to determine if spindle stop is active or disabled.
+// Define spindle stop override control states.
+#define SPINDLE_STOP_OVR_DISABLED       0  // Must be zero.
+#define SPINDLE_STOP_OVR_ENABLED        bit(0)
+#define SPINDLE_STOP_OVR_INITIATE       bit(1)
+#define SPINDLE_STOP_OVR_RESTORE        bit(2)
+#define SPINDLE_STOP_OVR_RESTORE_CYCLE  bit(3)
 
 
 // Define global system variables
@@ -137,9 +134,12 @@ typedef struct {
   uint8_t f_override;          // Feed rate override value in percent
   uint8_t r_override;          // Rapids override value in percent
   uint8_t spindle_speed_ovr;   // Spindle speed value in percent
-  uint8_t toggle_ovr_mask;          // Tracks toggle override states
+  uint8_t spindle_stop_ovr;    // Tracks spindle stop override states
   uint8_t report_ovr_counter;  // Tracks when to add override data to status reports.
   uint8_t report_wco_counter;  // Tracks when to add work coordinate offset data to status reports.
+  #ifdef VARIABLE_SPINDLE
+    float spindle_speed;
+  #endif
 } system_t;
 extern system_t sys;