doc/log/commit_log_v0.7.txt - grbl-v1.1h-fork - Gitiles

 ----------------
 Date: 2012-01-17
 Author: Sonny Jeon
 Subject: Update readme.textile

 ----------------
 Date: 2012-01-17
 Author: Sonny Jeon
 Subject: Merge pull request #47 from chamnit/v0_7

 Merging chamnit/v0_7 to grbl/master

 ----------------
 Date: 2012-01-17
 Author: Sonny Jeon
 Subject: Merge chamnit/v0_7 with grbl/master


 ----------------
 Date: 2012-01-17
 Author: Sonny Jeon
 Subject: Update readme.textile

 ----------------
 Date: 2012-01-17
 Author: Sonny Jeon
 Subject: Merge pull request #39 from chamnit/edge

 Merging chamnit/grbl edge v0.8a to grbl/grbl edge

 ----------------
 Date: 2012-01-15
 Author: Sonny Jeon
 Subject: Propagated premature step end bug fix from the edge branch. Updated printFloat() function.

 - Will not be uploading a hex build of this, unless asked.


 ----------------
 Date: 2012-01-15
 Author: Sonny Jeon
 Subject: Fix bug with premature step end. Refactored _delay_ms() and square() for better portability.

 - Fixed a premature step end bug dating back to Simen's 0.7b edge
 version is fixed, from which this code is forked from. Caused by Timer2
 constantly overflowing calling the Step Reset Interrupt every 128usec.
 Now Timer2 is always disabled after a step end and should free up some
 cycles for the main program. Could be more than one way to fix this
 problem. I'm open to suggestions.

 - _delay_ms() refactored to accept only constants to comply with
 current compilers. square() removed since not available with some
 compilers.


 ----------------
 Date: 2012-01-10
 Author: Sonny Jeon
 Subject: Extended position reporting with both home and work coordinates. Home position now retained after reset. Other minor changes/fixes.

 - Grbl now tracks both home and work (G92) coordinate systems and does
 live updates when G92 is called.
 - Rudimentary home and work position status reporting. Works but still
 under major construction.
 - Updated the main streaming script. Has a disabled periodic timer for
 querying status reports, disabled only because the Python timer doesn't
 consistently restart after the script exits. Add here only for user
 testing.
 - Fixed a bug to prevent an endless serial_write loop during status
 reports.
 - Refactored the planner variables to make it more clear what they are
 and make it easier for clear them.


 ----------------
 Date: 2012-01-09
 Author: Sonny Jeon
 Subject: Corrected a minor streaming script character counting bug.

 ----------------
 Date: 2012-01-09
 Author: Sonny Jeon
 Subject: Updated line in streaming script.

 ----------------
 Date: 2012-01-06
 Author: Sonny Jeon
 Subject: Position reporting, refactored system variables, serial print fixes, updated streaming scripts.

 - Added machine position reporting to status queries. This will be
 further developed with part positioning/offsets and maintaining
 location upon reset.

 - System variables refactored into a global struct for better
 readability.

 - Removed old obsolete Ruby streaming scripts. These were no longer
 compatible. Updated Python streaming scripts.

 - Fixed printFloat() and other printing functions.

 - Decreased planner buffer back to 18 blocks and increased TX serial
 buffer to 64 bytes. Need the memory space for future developments.

 - Begun adding run-time modes to grbl, where block delete toggle, mm/in
 reporting modes, jog modes, etc can be set during runtime. Will be
 fleshed out and placed into EEPROM when everything is added.


 ----------------
 Date: 2011-12-10
 Author: Sonny Jeon
 Subject: Various minor updates and variable definition corrections. Removed deprecated acceleration manager.

 - Removed deprecated acceleration manager (non-functional since v0.7b)
 - Updated variable types and function headers. - Updated stepper
 interrupt to ISR() from SIGNAL()+sei(). - General code cleanup.


 ----------------
 Date: 2011-12-08
 Author: Sonny Jeon
 Subject: Initial v0.8 ALPHA commit. Features multi-tasking run-time command execution (feed hold, cycle start, reset, status query). Extensive re-structuring of code for future features.

 - ALPHA status. - Multitasking ability with run-time command executions
 for real-time control and feedback. - Decelerating feed hold and resume
 during operation. - System abort/reset, which immediately kills all
 movement and re-initializes grbl. - Re-structured grbl to easily allow
 for new features: Status reporting, jogging, backlash compensation. (To
 be completed in the following releases.) - Resized TX/RX serial buffers
 (32/128 bytes) - Increased planner buffer size to 20 blocks. - Updated
 documentation.


 ----------------
 Date: 2011-11-19
 Author: Sonny Jeon
 Subject: Updated README and reordered branch versions.


 ----------------
 Date: 2011-11-19
 Author: Sonny Jeon
 Subject: Re-ordered stepper idle function to first disable interrupt.

 ----------------
 Date: 2011-11-11
 Author: Sonny Jeon
 Subject: Corrected clearing of target and position variable for the go home routine. Thanks Jens!

 ----------------
 Date: 2011-10-11
 Author: Sonny Jeon
 Subject: Delete a new work file shouldn't have been synced.


 ----------------
 Date: 2011-10-11
 Author: Sonny Jeon
 Subject: Third time's a charm! No more deceleration issues! Updated grbl version and settings. General cleanup.

 - Fleshed out the original idea to completely remove the long slope at
 the end of deceleration issue. This third time should absolutely
 eliminate it.
 - Changed the acceleration setting to kept as mm/min^2 internally,
 since this was creating unneccessary additional computation in the
 planner. Human readable value kept at mm/sec^2.
 - Updated grbl version 0.7d and settings version to 4. NOTE: Please
 check settings after update. These may have changed, but shouldn't.
 - Before updating the new features (pause, e-stop, federate override,
 etc), the edge branch will soon be merged with the master, barring any
 immediate issues that people may have, and the edge branch will be the
 testing ground for the new grbl version 0.8.


 ----------------
 Date: 2011-10-07
 Author: Sonny Jeon
 Subject: Forgot something! Comments on what the last change does.


 ----------------
 Date: 2011-10-06
 Author: Sonny Jeon
 Subject: Minor update to further eliminate the ole long slope deceleration issue. New update note!

 - Added another way to further ensure the long slope deceleration issue
 is eliminated. If the stepper rate change is too great near zero, the
 stepper rate is adjusted at half increments to the end of travel,
 creating a smooth transition. - If the new STEPPER_IDLE_LOCK_TIME is
 set as zero, this delay is not compiled at compile-time. - NOTE: The
 next update is likely going to be major, involving a full re-write of
 the stepper.c program to integrate a simple way to apply pauses,
 jogging, e-stop, and feedrate overrides. The interface should be
 flexible enough to be easily modified for use with either hardware
 switches or software commands. Coming soon.


 ----------------
 Date: 2011-09-29
 Author: Sonny Jeon
 Subject: Added complete stop delay at the end of all motion. Moved grbl preprocessor script into a new repository.

 Added a very short (25 ms) user-definable delay before the steppers are
 disabled at the motors are disabled and grbl goes idle. This ensures
 any residual inertia at the end of the last motion does not cause the
 axes to drift and grbl to lose its position when manually entering
 g-code or when performing a tool change and starting the next
 operation.


 ----------------
 Date: 2011-09-25
 Author: Sonny Jeon
 Subject: Updated some comments and fixed a bug in the new stepper logic.

 - The stepper logic was not initiating the decelerations for certain
 cases. Just re-arranged the logic to fix it.


 ----------------
 Date: 2011-09-24
 Author: Sonny Jeon
 Subject: Fixed long slope at deceleration issue. Moved things into config.h. New MINIMUM_PLANNER_SPEED parameter.

 - The long standing issue of a long slope at deceleration is likely
 fixed. The stepper program was not tracking and timing the end of
 acceleration and start of deceleration exactly and now is fixed to
 start and stop on time. Also, to ensure a better acceleration curve fit
 used by the planner, the stepper program delays the start of the
 accelerations by a half trapezoid tick to employ the midpoint rule. -
 Settings version 3 migration (not fully tested, but should work) -
 Added a MINIMUM_PLANNER_SPEED user-defined parameter to planner to let
 a user change this if problems arise for some reason. - Moved all
 user-definable #define parameters into config.h with clear comments on
 what they do and recommendations of how to change them. - Minor
 housekeeping.


 ----------------
 Date: 2011-09-18
 Author: Sonny J
 Subject: Fixed minor bugs in planner. Increased max dwell time. Long slope bug stop-gap solution note.

 - Fixed the planner TODO regarding minimum nominal speeds. Re-arranged
 calculations to be both more efficient and guaranteed to be greater
 than zero. - Missed a parenthesis location on the rate_delta
 calculation. Should fix a nearly in-perceptible issue with incorrect
 acceleration ramping in diagonal directions. - Increased maximum dwell
 time from 6.5sec to an 18hour max. A crazy amount more, but that's how
 the math works out. - Converted the internal feedrate values to mm/min
 only, as it was switching between mm/min to mm/sec and back to mm/min.
 Also added a feedrate > 0 check in gcode.c. - Identified the long slope
 at the end of rapid de/ac-celerations noted by stephanix. Problem with
 the numerical integration truncation error between the exact solution
 of estimate_acceleration_distance and how grbl actually performs the
 acceleration ramps discretely. Increasing the
 ACCELERATION_TICKS_PER_SECOND in config.h helps fix this problem.
 Investigating further.


 ----------------
 Date: 2011-09-15
 Author: Sonny J
 Subject: More '%' modulo opertor removals and some housecleaning.

 - Serial functions contained quite a few modulo operations that would
 be executed with high frequency when streaming. AVR processors are very
 slow when operating these. In one test on the Arduino forums, it showed
 about a 15x slow down compared to a simple if-then statement. -
 Clarified some variable names and types and comments.


 ----------------
 Date: 2011-09-13
 Author: Sonny J
 Subject: Further planner improvements and misc minor bug fixes. Memory savings and increased buffer size.

 - Update grbl version and settings version to automatically reset
 eeprom. FYI, this will reset your grbl settings. - Saved
 3*BLOCK_BUFFER_SIZE doubles in static memory by removing obsolete
 variables: speed_x, speed_y, and speed_z. - Increased buffer size
 conservatively to 18 from 16. (Probably can do 20). - Removed expensive!
 modulo operator from block indexing function. Reduces significant
 computational overhead. - Re-organized some sqrt() calls to be more
 efficient during time critical planning cases, rather than non-time
 critical. - Minor bug fix in planner max junction velocity logic. -
 Simplified arc logic and removed need to multiply for CW or CCW
 direction.


 ----------------
 Date: 2011-09-06
 Author: Sonny J
 Subject: Optimized planner re-write. Significantly faster. Full arc support enabled by rotation matrix approach.

 - Significant improvements in the planner. Removed or reordered
 repetitive and expensive calculations by order of importance:
 recalculating unchanged blocks, trig functions [sin(), cos(), tan()],
 sqrt(), divides, and multiplications. Blocks long enough for nominal
 speed to be guaranteed to be reached ignored by planner. Done by
 introducing two uint8_t flags per block. Reduced computational overhead
 by an order of magnitude.   - Arc motion generation completely
 re-written and optimized. Now runs with acceleration planner. Removed
 all but one trig function (atan2) from initialization. Streamlined
 computations. Segment target locations generated by vector
 transformation and small angle approximation. Arc path correction
 implemented for accumulated error of approximation and single precision
 calculation of Arduino. Bug fix in message passing.


 ----------------
 Date: 2011-09-04
 Author: Sonny J
 Subject: Minor update for memory savings in ring buffer and fleshed out commenting.

 No changes in functionality. Path vectors moved from ring buffer to
 local planner static variables to save 3*(BUFFER_SIZE - 1) doubles in
 memory. Detailed comments. Really need to stop micro-updating. Should be
 the last until a planner optimization (ala Jens Geisler) has been
 completed.


 ----------------
 Date: 2011-09-04
 Author: Sonny J
 Subject: More minor bug fixes in planner.

 Reverse planner was over-writing the initial/buffer tail entry speed,
 which reset the forward planner and caused it to lose track of its
 speed. Should now accelerate into short linear segments much nicer now.


 ----------------
 Date: 2011-09-03
 Author: Sonny J
 Subject: Minor bug fixes in planner.


 ----------------
 Date: 2011-09-03
 Author: Sonny J
 Subject: Add G02/03 arc conversion/pre-processor script and example streaming script

 Beta pre-processor script used to clean and streamline g-code for
 streaming and converts G02/03 arcs into linear segments. Allows for full
 acceleration support if the pre-processed g-code is then streamed to
 grill, sans G02/03 arcs. Added a simple example streaming script for
 Python users.


 ----------------
 Date: 2011-09-03
 Author: Sonny J
 Subject: Significantly improved junction control and fixed computation bugs in planner

 - Junction jerk now re-defined as junction_deviation. The distance from
 the junction to the edge of a circle tangent to both previous and
 current path lines. The circle radii is used to compute the maximum
 junction velocity by centripetal acceleration. More robust and
 simplified way to compute jerk.   - Fixed bugs related to entry and exit
 factors. They were computed based on the current nominal speeds but not
 when computing exit factors for neighboring blocks. Removed factors and
 replaced with entry speeds only. Factors now only computed for stepper
 trapezoid rate conversions.  - Misc: Added min(), next_block_index,
 prev_block_index functions for clarity.


 ----------------
 Date: 2011-08-15
 Author: Sonny J
 Subject: Moved comment and block delete handling into protocol.c from gcode.c. Fixes bug when comment and block delete are not isolated. Blank lines ignored.

 Comments, block delete characters, and blank lines are no longer passed
 to the gcode parser and should free up some memory by ignoring these
 characters. Gcode parser now expects clean gcode only. There was a bug
 if there were block deletes or comments not in the first character (i.e.
 spindle on/off for proofing geode without turning it on, or a NXX
 followed by a comment). This should fix it by bypassing the problem.
 Left a commented line for easily turning on and off block deletes for a
 later feature, if desired.


 ----------------
 Date: 2011-08-15
 Author: Sonny J
 Subject: Revert ea5b8942db2616e93fc0478922010c3bab7c0481^..HEAD


 ----------------
 Date: 2011-08-15
 Author: Sonny J
 Subject: Moved comment and block delete handling into protocol.c from gcode.c. Fixes bug when comment and block delete are not isolated. Blank lines ignored.

 Comments, block delete characters, and blank lines are no longer passed
 to the gcode parser and should free up some memory by ignoring these
 characters. Gcode parser now expects clean gcode only. There was a bug
 if there were block deletes or comments not in the first character (i.e.
 spindle on/off for proofing geode without turning it on, or a NXX
 followed by a comment). This should fix it by bypassing the problem.
 Left a commented line for easily turning on and off block deletes for a
 later feature, if desired.


 ----------------
 Date: 2011-08-15
 Author: Sonny J
 Subject: Revert 517a0f659a06182c89cafe27ee371edccad777a4^..HEAD


 ----------------
 Date: 2011-08-15
 Author: Sonny J
 Subject: Revert "Moved comment and block delete handling to be done in protocol.c rather than gcode.c. Prevents these from being held in memory. Also, fixes bug when comments and block delete character are mixed with g-code."

 This reverts commit ea5b8942db2616e93fc0478922010c3bab7c0481.


 ----------------
 Date: 2011-08-15
 Author: Sonny J
 Subject: Revert fdc90f1821f1f5edb7756fcddce75b4b4fbf6bbf^..HEAD


 ----------------
 Date: 2011-08-15
 Author: chamnit
 Subject: Removed comment and block delete handling from gcode.c. Parser expects clean gcode.

 ----------------
 Date: 2011-08-15
 Author: chamnit
 Subject: Moved comment and block delete handling to be done in protocol.c rather than gcode.c. Prevents these from being held in memory. Also, fixes bug when comments and block delete character are mixed with g-code.
	----------------
	Date: 2012-01-17
	Author: Sonny Jeon
	Subject: Update readme.textile

	----------------
	Date: 2012-01-17
	Author: Sonny Jeon
	Subject: Merge pull request #47 from chamnit/v0_7

	Merging chamnit/v0_7 to grbl/master

	----------------
	Date: 2012-01-17
	Author: Sonny Jeon
	Subject: Merge chamnit/v0_7 with grbl/master


	----------------
	Date: 2012-01-17
	Author: Sonny Jeon
	Subject: Update readme.textile

	----------------
	Date: 2012-01-17
	Author: Sonny Jeon
	Subject: Merge pull request #39 from chamnit/edge

	Merging chamnit/grbl edge v0.8a to grbl/grbl edge

	----------------
	Date: 2012-01-15
	Author: Sonny Jeon
	Subject: Propagated premature step end bug fix from the edge branch. Updated printFloat() function.

	- Will not be uploading a hex build of this, unless asked.


	----------------
	Date: 2012-01-15
	Author: Sonny Jeon
	Subject: Fix bug with premature step end. Refactored _delay_ms() and square() for better portability.

	- Fixed a premature step end bug dating back to Simen's 0.7b edge
	version is fixed, from which this code is forked from. Caused by Timer2
	constantly overflowing calling the Step Reset Interrupt every 128usec.
	Now Timer2 is always disabled after a step end and should free up some
	cycles for the main program. Could be more than one way to fix this
	problem. I'm open to suggestions.

	- _delay_ms() refactored to accept only constants to comply with
	current compilers. square() removed since not available with some
	compilers.


	----------------
	Date: 2012-01-10
	Author: Sonny Jeon
	Subject: Extended position reporting with both home and work coordinates. Home position now retained after reset. Other minor changes/fixes.

	- Grbl now tracks both home and work (G92) coordinate systems and does
	live updates when G92 is called.
	- Rudimentary home and work position status reporting. Works but still
	under major construction.
	- Updated the main streaming script. Has a disabled periodic timer for
	querying status reports, disabled only because the Python timer doesn't
	consistently restart after the script exits. Add here only for user
	testing.
	- Fixed a bug to prevent an endless serial_write loop during status
	reports.
	- Refactored the planner variables to make it more clear what they are
	and make it easier for clear them.


	----------------
	Date: 2012-01-09
	Author: Sonny Jeon
	Subject: Corrected a minor streaming script character counting bug.

	----------------
	Date: 2012-01-09
	Author: Sonny Jeon
	Subject: Updated line in streaming script.

	----------------
	Date: 2012-01-06
	Author: Sonny Jeon
	Subject: Position reporting, refactored system variables, serial print fixes, updated streaming scripts.

	- Added machine position reporting to status queries. This will be
	further developed with part positioning/offsets and maintaining
	location upon reset.

	- System variables refactored into a global struct for better
	readability.

	- Removed old obsolete Ruby streaming scripts. These were no longer
	compatible. Updated Python streaming scripts.

	- Fixed printFloat() and other printing functions.

	- Decreased planner buffer back to 18 blocks and increased TX serial
	buffer to 64 bytes. Need the memory space for future developments.

	- Begun adding run-time modes to grbl, where block delete toggle, mm/in
	reporting modes, jog modes, etc can be set during runtime. Will be
	fleshed out and placed into EEPROM when everything is added.


	----------------
	Date: 2011-12-10
	Author: Sonny Jeon
	Subject: Various minor updates and variable definition corrections. Removed deprecated acceleration manager.

	- Removed deprecated acceleration manager (non-functional since v0.7b)
	- Updated variable types and function headers. - Updated stepper
	interrupt to ISR() from SIGNAL()+sei(). - General code cleanup.


	----------------
	Date: 2011-12-08
	Author: Sonny Jeon
	Subject: Initial v0.8 ALPHA commit. Features multi-tasking run-time command execution (feed hold, cycle start, reset, status query). Extensive re-structuring of code for future features.

	- ALPHA status. - Multitasking ability with run-time command executions
	for real-time control and feedback. - Decelerating feed hold and resume
	during operation. - System abort/reset, which immediately kills all
	movement and re-initializes grbl. - Re-structured grbl to easily allow
	for new features: Status reporting, jogging, backlash compensation. (To
	be completed in the following releases.) - Resized TX/RX serial buffers
	(32/128 bytes) - Increased planner buffer size to 20 blocks. - Updated
	documentation.


	----------------
	Date: 2011-11-19
	Author: Sonny Jeon
	Subject: Updated README and reordered branch versions.


	----------------
	Date: 2011-11-19
	Author: Sonny Jeon
	Subject: Re-ordered stepper idle function to first disable interrupt.

	----------------
	Date: 2011-11-11
	Author: Sonny Jeon
	Subject: Corrected clearing of target and position variable for the go home routine. Thanks Jens!

	----------------
	Date: 2011-10-11
	Author: Sonny Jeon
	Subject: Delete a new work file shouldn't have been synced.


	----------------
	Date: 2011-10-11
	Author: Sonny Jeon
	Subject: Third time's a charm! No more deceleration issues! Updated grbl version and settings. General cleanup.

	- Fleshed out the original idea to completely remove the long slope at
	the end of deceleration issue. This third time should absolutely
	eliminate it.
	- Changed the acceleration setting to kept as mm/min^2 internally,
	since this was creating unneccessary additional computation in the
	planner. Human readable value kept at mm/sec^2.
	- Updated grbl version 0.7d and settings version to 4. NOTE: Please
	check settings after update. These may have changed, but shouldn't.
	- Before updating the new features (pause, e-stop, federate override,
	etc), the edge branch will soon be merged with the master, barring any
	immediate issues that people may have, and the edge branch will be the
	testing ground for the new grbl version 0.8.


	----------------
	Date: 2011-10-07
	Author: Sonny Jeon
	Subject: Forgot something! Comments on what the last change does.


	----------------
	Date: 2011-10-06
	Author: Sonny Jeon
	Subject: Minor update to further eliminate the ole long slope deceleration issue. New update note!

	- Added another way to further ensure the long slope deceleration issue
	is eliminated. If the stepper rate change is too great near zero, the
	stepper rate is adjusted at half increments to the end of travel,
	creating a smooth transition. - If the new STEPPER_IDLE_LOCK_TIME is
	set as zero, this delay is not compiled at compile-time. - NOTE: The
	next update is likely going to be major, involving a full re-write of
	the stepper.c program to integrate a simple way to apply pauses,
	jogging, e-stop, and feedrate overrides. The interface should be
	flexible enough to be easily modified for use with either hardware
	switches or software commands. Coming soon.


	----------------
	Date: 2011-09-29
	Author: Sonny Jeon
	Subject: Added complete stop delay at the end of all motion. Moved grbl preprocessor script into a new repository.

	Added a very short (25 ms) user-definable delay before the steppers are
	disabled at the motors are disabled and grbl goes idle. This ensures
	any residual inertia at the end of the last motion does not cause the
	axes to drift and grbl to lose its position when manually entering
	g-code or when performing a tool change and starting the next
	operation.


	----------------
	Date: 2011-09-25
	Author: Sonny Jeon
	Subject: Updated some comments and fixed a bug in the new stepper logic.

	- The stepper logic was not initiating the decelerations for certain
	cases. Just re-arranged the logic to fix it.


	----------------
	Date: 2011-09-24
	Author: Sonny Jeon
	Subject: Fixed long slope at deceleration issue. Moved things into config.h. New MINIMUM_PLANNER_SPEED parameter.

	- The long standing issue of a long slope at deceleration is likely
	fixed. The stepper program was not tracking and timing the end of
	acceleration and start of deceleration exactly and now is fixed to
	start and stop on time. Also, to ensure a better acceleration curve fit
	used by the planner, the stepper program delays the start of the
	accelerations by a half trapezoid tick to employ the midpoint rule. -
	Settings version 3 migration (not fully tested, but should work) -
	Added a MINIMUM_PLANNER_SPEED user-defined parameter to planner to let
	a user change this if problems arise for some reason. - Moved all
	user-definable #define parameters into config.h with clear comments on
	what they do and recommendations of how to change them. - Minor
	housekeeping.


	----------------
	Date: 2011-09-18
	Author: Sonny J
	Subject: Fixed minor bugs in planner. Increased max dwell time. Long slope bug stop-gap solution note.

	- Fixed the planner TODO regarding minimum nominal speeds. Re-arranged
	calculations to be both more efficient and guaranteed to be greater
	than zero. - Missed a parenthesis location on the rate_delta
	calculation. Should fix a nearly in-perceptible issue with incorrect
	acceleration ramping in diagonal directions. - Increased maximum dwell
	time from 6.5sec to an 18hour max. A crazy amount more, but that's how
	the math works out. - Converted the internal feedrate values to mm/min
	only, as it was switching between mm/min to mm/sec and back to mm/min.
	Also added a feedrate > 0 check in gcode.c. - Identified the long slope
	at the end of rapid de/ac-celerations noted by stephanix. Problem with
	the numerical integration truncation error between the exact solution
	of estimate_acceleration_distance and how grbl actually performs the
	acceleration ramps discretely. Increasing the
	ACCELERATION_TICKS_PER_SECOND in config.h helps fix this problem.
	Investigating further.


	----------------
	Date: 2011-09-15
	Author: Sonny J
	Subject: More '%' modulo opertor removals and some housecleaning.

	- Serial functions contained quite a few modulo operations that would
	be executed with high frequency when streaming. AVR processors are very
	slow when operating these. In one test on the Arduino forums, it showed
	about a 15x slow down compared to a simple if-then statement. -
	Clarified some variable names and types and comments.


	----------------
	Date: 2011-09-13
	Author: Sonny J
	Subject: Further planner improvements and misc minor bug fixes. Memory savings and increased buffer size.

	- Update grbl version and settings version to automatically reset
	eeprom. FYI, this will reset your grbl settings. - Saved
	3*BLOCK_BUFFER_SIZE doubles in static memory by removing obsolete
	variables: speed_x, speed_y, and speed_z. - Increased buffer size
	conservatively to 18 from 16. (Probably can do 20). - Removed expensive!
	modulo operator from block indexing function. Reduces significant
	computational overhead. - Re-organized some sqrt() calls to be more
	efficient during time critical planning cases, rather than non-time
	critical. - Minor bug fix in planner max junction velocity logic. -
	Simplified arc logic and removed need to multiply for CW or CCW
	direction.


	----------------
	Date: 2011-09-06
	Author: Sonny J
	Subject: Optimized planner re-write. Significantly faster. Full arc support enabled by rotation matrix approach.

	- Significant improvements in the planner. Removed or reordered
	repetitive and expensive calculations by order of importance:
	recalculating unchanged blocks, trig functions [sin(), cos(), tan()],
	sqrt(), divides, and multiplications. Blocks long enough for nominal
	speed to be guaranteed to be reached ignored by planner. Done by
	introducing two uint8_t flags per block. Reduced computational overhead
	by an order of magnitude. - Arc motion generation completely
	re-written and optimized. Now runs with acceleration planner. Removed
	all but one trig function (atan2) from initialization. Streamlined
	computations. Segment target locations generated by vector
	transformation and small angle approximation. Arc path correction
	implemented for accumulated error of approximation and single precision
	calculation of Arduino. Bug fix in message passing.


	----------------
	Date: 2011-09-04
	Author: Sonny J
	Subject: Minor update for memory savings in ring buffer and fleshed out commenting.

	No changes in functionality. Path vectors moved from ring buffer to
	local planner static variables to save 3*(BUFFER_SIZE - 1) doubles in
	memory. Detailed comments. Really need to stop micro-updating. Should be
	the last until a planner optimization (ala Jens Geisler) has been
	completed.


	----------------
	Date: 2011-09-04
	Author: Sonny J
	Subject: More minor bug fixes in planner.

	Reverse planner was over-writing the initial/buffer tail entry speed,
	which reset the forward planner and caused it to lose track of its
	speed. Should now accelerate into short linear segments much nicer now.


	----------------
	Date: 2011-09-03
	Author: Sonny J
	Subject: Minor bug fixes in planner.


	----------------
	Date: 2011-09-03
	Author: Sonny J
	Subject: Add G02/03 arc conversion/pre-processor script and example streaming script

	Beta pre-processor script used to clean and streamline g-code for
	streaming and converts G02/03 arcs into linear segments. Allows for full
	acceleration support if the pre-processed g-code is then streamed to
	grill, sans G02/03 arcs. Added a simple example streaming script for
	Python users.


	----------------
	Date: 2011-09-03
	Author: Sonny J
	Subject: Significantly improved junction control and fixed computation bugs in planner

	- Junction jerk now re-defined as junction_deviation. The distance from
	the junction to the edge of a circle tangent to both previous and
	current path lines. The circle radii is used to compute the maximum
	junction velocity by centripetal acceleration. More robust and
	simplified way to compute jerk. - Fixed bugs related to entry and exit
	factors. They were computed based on the current nominal speeds but not
	when computing exit factors for neighboring blocks. Removed factors and
	replaced with entry speeds only. Factors now only computed for stepper
	trapezoid rate conversions. - Misc: Added min(), next_block_index,
	prev_block_index functions for clarity.


	----------------
	Date: 2011-08-15
	Author: Sonny J
	Subject: Moved comment and block delete handling into protocol.c from gcode.c. Fixes bug when comment and block delete are not isolated. Blank lines ignored.

	Comments, block delete characters, and blank lines are no longer passed
	to the gcode parser and should free up some memory by ignoring these
	characters. Gcode parser now expects clean gcode only. There was a bug
	if there were block deletes or comments not in the first character (i.e.
	spindle on/off for proofing geode without turning it on, or a NXX
	followed by a comment). This should fix it by bypassing the problem.
	Left a commented line for easily turning on and off block deletes for a
	later feature, if desired.


	----------------
	Date: 2011-08-15
	Author: Sonny J
	Subject: Revert ea5b8942db2616e93fc0478922010c3bab7c0481^..HEAD


	----------------
	Date: 2011-08-15
	Author: Sonny J
	Subject: Moved comment and block delete handling into protocol.c from gcode.c. Fixes bug when comment and block delete are not isolated. Blank lines ignored.

	Comments, block delete characters, and blank lines are no longer passed
	to the gcode parser and should free up some memory by ignoring these
	characters. Gcode parser now expects clean gcode only. There was a bug
	if there were block deletes or comments not in the first character (i.e.
	spindle on/off for proofing geode without turning it on, or a NXX
	followed by a comment). This should fix it by bypassing the problem.
	Left a commented line for easily turning on and off block deletes for a
	later feature, if desired.


	----------------
	Date: 2011-08-15
	Author: Sonny J
	Subject: Revert 517a0f659a06182c89cafe27ee371edccad777a4^..HEAD


	----------------
	Date: 2011-08-15
	Author: Sonny J
	Subject: Revert "Moved comment and block delete handling to be done in protocol.c rather than gcode.c. Prevents these from being held in memory. Also, fixes bug when comments and block delete character are mixed with g-code."

	This reverts commit ea5b8942db2616e93fc0478922010c3bab7c0481.


	----------------
	Date: 2011-08-15
	Author: Sonny J
	Subject: Revert fdc90f1821f1f5edb7756fcddce75b4b4fbf6bbf^..HEAD


	----------------
	Date: 2011-08-15
	Author: chamnit
	Subject: Removed comment and block delete handling from gcode.c. Parser expects clean gcode.

	----------------
	Date: 2011-08-15
	Author: chamnit
	Subject: Moved comment and block delete handling to be done in protocol.c rather than gcode.c. Prevents these from being held in memory. Also, fixes bug when comments and block delete character are mixed with g-code.