grbl/doc/log/commit_log_v1.1.txt

----------------
Date: 2019-08-30
Author: Sonny Jeon
Subject: Fixed typo bug effecting dual-axis build with Y.


----------------
Date: 2019-08-25
Author: Sonny Jeon
Subject: Update grbl.h


----------------
Date: 2019-08-25
Author: Sonny Jeon
Subject: Update system.c


----------------
Date: 2019-07-30
Author: Sonny Jeon
Subject: Dual motor support for self-squaring gantry homing.

- New dual motor support feature for gantry CNC machines. An axis motor is  efficiently mirrored to a dedicated set of step and direction pins (D12/D13 or A3/A4) with no detectable loss of performance. Primarily used to independently home both sides of a dual-motor gantry with a pair of limit switches (second shared with Z-axis limit pin). When the limit switches are setup correctly, Grbl will self-square the gantry (and stay square if $1=255 is programmed). Beware use at your own risk! Grbl is not responsible for any damage to any machines.

- Dual axis motors is only supported on the X-axis or Y-axis. And deletes the spindle direction(D13) and optional coolant mist (A4) features to make room for the dual motor step and direction pins.

- Dual axis homing will automatically abort homing if one limit switch triggers and travels more than 5% (default) of the non-dual axis max travel setting. For example, if the X-axis has dual motors and one X-axis triggers during homing, Grbl will abort 5% of the Y-axis max travel and the other X-axis limit fails to trigger. This will help keep any misconfigurations or failed limit switches from damaging the machine, but not completely eliminate this risk. Please take all precautions and test thouroughly before using this.

- Dual axis motors supports two configurations:

- Support for Arduino CNC shield clones. For these, step/dir on pins D12/D13, and spindle enable is moved to A3 (old coolant enable), while coolant enable is moved to A4 (SDA pin). Variable spindle/laser mode option is NOT supported for this shield.

- Support for Protoneer CNC Shield v3.51. Step/dir on pins A3/A4, and  coolant enable is moved to D13 (old spindle direction pin). Variable spindle/laser mode option IS supported for this shield.

- Added Bob's CNC E3 and E4 CNC machine defaults.


----------------
Date: 2018-11-12
Author: Sonny Jeon
Subject: Update grbl.h

----------------
Date: 2018-11-12
Author: Sonny Jeon
Subject: Update system.c

Correct control pin state checking within pin change interrupt. Improper if-else statements could lead to missed signal.

----------------
Date: 2018-11-12
Author: Sonny Jeon
Subject: Update gcode.c

If statement bug fix related to jog motion modal group error checking.

----------------
Date: 2018-06-14
Author: Sonny Jeon
Subject: Spindle/coolant rare bug fixes. Free more flash.

[new] Altered the way default settings are stored and restored. Saved about 300 bytes(!) of flashed size. Should free up enough for certain configurations of CoreXY machines.

[fix] When the optional M7 mist coolant IO was enabled, coolant overrides was not disabling correctly.

[fix] Coolant override states was not restored correctly after a parking motion in certain situations. It would restore programmed state, rather than current overridden state.

[fix] Now allow coolant overrides to operate during jogging motion.

[fix] Invert control pin mask typo.

[new] Added a new build info feedback mechanism for enabling the safety door input pin.


----------------
Date: 2018-06-09
Author: Jon
Subject: Fix apparent error in restore masking that causes the call to coolant_set_state to not re-enable the mist (M7) output if it was previously enabled. (#469)



----------------
Date: 2018-04-06
Author: Sonny Jeon
Subject: Updated instructions in fit_nonlinear_spindle.py

- repl.it has changed since the last time fit_nonlinear_spindle.py was tested. Updated instructions.


----------------
Date: 2017-08-01
Author: Sonny Jeon
Subject: Improved fix for rare lowering feed/rapid override bug.

[fix] In the previous hot fix, there was still (rarer) potential for
very small floating point errors incorrectly handle an override
deceleration and crash Grbl. Re-factored the if-then statement in terms
of speed changes, rather than distance, to completely eliminate the
issue.


----------------
Date: 2017-07-31
Author: Sonny Jeon
Subject: Hot fix for rare lowering feed override bug.

[fix] Squashed a very rare bug when lowering the feedrate (or rapid) override. When in the very strict set of circumstances with acceleration settings, override step size, and current speed, an internal calculation would cause Grbl to crash. The fix was an overlooked equality statement that should have been a less than or equal, not a less than.


----------------
Date: 2017-07-17
Author: Sonny Jeon
Subject: Clean up and new streaming script check-mode feature.

[new] The stream.py streaming script now has a check-mode option, where it will place Grbl in $C check mode automatically and then stream the g-code program. It's a very fast way to check if the g-code program has any errors.

[fix] The debug variable was not initialized if the debug option was enabled in config.h

[fix] Updated error_codes CSV file to the same format as the others.


----------------
Date: 2017-05-31
Author: chamnit
Subject: New nonlinear spindle speed PWM output model and solution. Updated scripts.

[new] A nonlinear spindle speed/PWM output option via a piecewise
linear fit model. Enabled through config.h and solved by a Python
script in /doc/script

[new] fit_nonlinear_spindle.py. A solver script that can be run on
http://repl.it for free. No Python install necessary. All instructions
are available in the script file comments.

[new] stream.py has been updated to include status reports feedback at
1 second interval.

[fix] stream.py bug fix with verbose mode disabled.


----------------
Date: 2017-03-24
Author: Sonny Jeon
Subject: Added an error code for laser mode when VARIABLE_SPINDLE is disabled.

- When trying to enable laser mode with $32=1 and VARIABLE_SPINDLE is
disabled, the error code shown was improperly stating it was a homing
failure. Added an new error code specifically for the laser mode being
disabled without VARIABLE_SPINDLE.


----------------
Date: 2017-03-19
Author: Sonny Jeon
Subject: Housekeeping.

- Moved Grbl logo files to a separate repo.

- Added PocketNC FR4 defaults. Needs some additional work though to be
compatible.

- Updated README image links.


----------------
Date: 2017-03-19
Author: Sonny Jeon
Subject: Update README.md

----------------
Date: 2017-03-02
Author: Sonny Jeon
Subject: Fixed $G report issue with M7 and M8 both enabled.

[fix] When M7 and M8 are both enabled, $G report would show `M78`,
rather than `M7 M8`. This only effects systems that enable M7 mist
coolant in config.h. Not the default build.


----------------
Date: 2017-02-27
Author: Sonny Jeon
Subject: Fixed shared build info code.

- The build info options of “two switches on an axis” and “homing init
lock” shared the same letter ‘L’. The former is now ’T’.


----------------
Date: 2017-02-23
Author: Sonny Jeon
Subject: Restrict coincident target updates to M3 constant laser only.

- Restrict M3 forced updates when there is a motion block with a
coincident target. Force syncing of the spindle state can lead to some
pauses during a job that has coincident targets. That’s not
particularly desirable. This ensures M4 dynamic mode is not effected by
this force-sync.


----------------
Date: 2017-02-23
Author: Sonny Jeon
Subject: Fixed issue with M3 laser state changes and coincident targets.

[fix] When in M3 constant laser power mode, a change from G0 to G1
would not set the laser on, if G1 was passed with a coincident target.
Motion controller now checks for a coincident target situation and will
force a spindle sync when detected.


----------------
Date: 2017-01-31
Author: Sonny Jeon
Subject: Additional build info in the $I printout.

- [new] Added total available planner buffer blocks (15 shown, but
there are 16. one is used by the ring buffer and to execute system
motions) and serial RX buffer bytes. This information is useful for
GUIs to setup and optimize their streaming protocols easily.

[doc] Updated the interface document to reflect the change.


----------------
Date: 2017-01-29
Author: Sonny Jeon
Subject: Tidying up parking override control implementation

[new] Added a default configuration for the parking override control
upon a reset or power-up. By default, parking is enabled, but this may
be disabled via a config.h option.

[fix] Parking override control should be checking if the command word
is passed, rather than the value.


----------------
Date: 2017-01-28
Author: chamnit
Subject: v1.1f. Parking override control. Spindle enable pin option.

[ver] v1.1f update due to tweaks to interface from new parking override
control.

[new] Parking motion override control via new `M56 P0` and `M56 P1`
command, which disables and enables the parking motion, respectively.
Requires ENABLE_PARKING_OVERRIDE_CONTROL and PARKING_ENABLE enabled in
config.h. Primarily for OEMs.

[new] `M56` appears in the $G report when enabled.

[new] Five new build info identification letters. Some were missing and
a couple are new. Updated the CSV and documentation to reflect these
new items.

[new] Spindle enable pin configuration option to alter its behavior
based on how certain lasers work. By default, Grbl treats the enable
pin separately and leaves it on when S is 0. The new option turns the
enable pin on and off with S>0 and S=0. This only is in effect when a
user enables the USE_SPINDLE_DIR_AS_ENABLE_PIN option.

[fix] M4 is now allowed to work when USE_SPINDLE_DIR_AS_ENABLE_PIN is
enabled. Previously this was blocked and was problematic for laser
folks using M4.

[fix] Properly declared system variables as extern. Not sure how that
went unnoticed or why it worked up until now but it has.

[fix] EXTREMELY RARE. When AMASS is intentionally disabled and sent a
motion command that is _one step_ in length, Grbl would not actuate the
step due to numerical round-off. Applied a fix to prevent the round-off
issue.

[fix] Added a compile-time check for AMASS settings to make sure that
the numerical round-off issue doesn’t effect it. This would only happen
if someone set AMASS max levels to zero. It does not effect AMASS with
its current defaults.

[fix] Wrapped the mc_parking_motion() function in an ifdef for porting
purposes.

[fix] Fixed an issue when in inverse time mode and G0’s would require a
F word. This was not correct.

[fix] Added a note in the defaults.h file that MAX_TRAVEL values must
be positive. Some users were setting this negative and it was causing
issues.


----------------
Date: 2017-01-14
Author: Sonny Jeon
Subject: Tool number bug fix. Updated documentation.

- [fix] Tool numbers were not being tracked and reported correctly. Now
shows tool number values in $G when programmed.

- [fix] Added a max tool number value check to the g-code parser.

- [doc] Added a new error code for invalid tool number. Updated CSV and
interface documents.

- [doc] Added a implementation note for buffer state in status reports.
Don’t rely on this data for streaming.


----------------
Date: 2017-01-03
Author: Sonny Jeon
Subject: Spindle enable pin with variable spindle option fix.

- [fix] When USE_SPINDLE_DIR_AS_ENABLE_PIN is enabled in config.h, the
enable pin was not being set when spindle speed is zero. This behavior
should now be fixed.


----------------
Date: 2016-12-19
Author: Sonny Jeon
Subject: Fixed homing fail alarm handling. Re-integrated software debouncing.

- [bug] Fixed a homing fail issue, where the alarm was not being set
right, not cleared correctly. It would report the wrong code and enter
an infinite alarm loop. This was due to how alarm codes were altered a
while back. Now updated and fixed to show the right codes.

- [feature] Re-installed optional software debouncing for hard limit
switches. By request.


----------------
Date: 2016-12-18
Author: Sonny Jeon
Subject: Addressed optional PWM min value issue. Updated docs.

- [fix] Spindle PWM minimum value had some typos. Fixed the macros to
compile correctly. Only effects users that enable SPINDLE_MINIMUM_PWM.
The name changed to SPINDLE_PWM_MIN_VALUE for consistency sake.

- Updated the laser documentation.


----------------
Date: 2016-12-12
Author: Sonny Jeon
Subject: Updating steam.py streaming script

- Added push message capability to the stream.py streaming script. It
prints out as a `Debug:` string in the output.


----------------
Date: 2016-12-11
Author: Sonny Jeon
Subject: Updated documentation.


----------------
Date: 2016-12-10
Author: Sonny Jeon
Subject: Updated documentation. Cleaned up a bit.

- [doc] Updated the markdown documents for the v1.1 release.

- [doc] Removed references to classic GUI mode.


----------------
Date: 2016-12-09
Author: Sonny Jeon
Subject: Update README.md

----------------
Date: 2016-12-09
Author: Sonny Jeon
Subject: Update README.md

----------------
Date: 2016-12-09
Author: Sonny Jeon
Subject: Update README.md

----------------
Date: 2016-12-08
Author: Sonny Jeon
Subject: Removed classic GUI interface. Fixed typo with line number support.

- [config] Permanently removed classic GUI interface support. This
unintentionally created a problem where some users/GUI devs used this
compatibility mode and did not update to the new interface. So, there
were two interfaces in use, rather than just one like it was intended.
This removal should help everyone by forcing all GUIs to update and
updated GUI not having to support yet another interface.

- Fixed typo with line number support in jog mode.


----------------
Date: 2016-12-04
Author: chamnit
Subject: Fixed unintended laser mode pausing. Updated documentation. Min SS OVR lowered to 10%.

- [laser] Tested a working version and pushed the wrong one for the
last! 20161203 was pausing upon every spindle speed change. That’s not
right. Fixed so nearly all motions are passed through and does not stop.

- Minimum spindle speed override lower from 50% to 10%. Lasers could
use the lower speeds.

- Fixed a very minor bug related to G80 error checking. Allowed no
error with non-modal motions with axis words. Not correct and fixed.

- Fixed a compile error when disabling VARIABLE_SPINDLE

- [doc] Updated some obsolete documentation.

- [doc] Started a “Laser Mode” document that summarizes how Grbl’s new
laser mode works.


----------------
Date: 2016-12-03
Author: Sonny Jeon
Subject: v1.1e: New laser features. G-code parser refactoring. CoreXY homing fix.

- Increment to v1.1e due to new laser features.

- After several discussions with some prominent laser people, a few
tweaks to the new laser mode has been installed.

- LASER: M3 behaves in a constant power mode.

- LASER: M4 behaves in a dynamic power mode, where the laser power is
automatically adjusted based on how fast Grbl is moving relative to the
programmed feed rate. This is the same as the  CONSTANT_POWER_PER_RATE
config.h option in the last version. NOTE: When not in motion in M4,
Grbl automatically turns off the laser. Again, it only operates while
moving!

- LASER: Only G1, G2, and G3 motion modes will turn on the laser. So,
this means that G0, G80 motion modes will always keep the laser
disabled. No matter if M3/M4 are active!

- LASER: A spindle stop override is automatically invoked when a laser
is put in a feed hold. This behavior may be disabled by a config.h
option.

- Lots of little tweaks to the g-code parser to help streamline it a
bit. It should no effect how it operates. Generally just added a parser
flag to track and execute certain scenarios a little more clearly.

- Jog motions now allow line numbers to be passed to it and will be
displayed in the status reports.

- Fixed a CoreXY homing bug.

- Fixed an issue when $13 is changed, WCO isn’t sent immediately.

- Altered how spindle PWM is set in the stepper ISR. Updated on a step
segment basis now. May need to change this back if there are any
oddities from doing this.

- Updated some documentation. Clarified why M0 no longer showing up in
$G and why a `1.` floating point values are shown with no decimals,
like so `1`.


----------------
Date: 2016-11-12
Author: Sonny Jeon
Subject: PWM calculation correction.

- The PWM calculation was a little bit off and has been corrected.

- Edited the unused settings strings to be smaller and just show what
the settings are, rather than include units. May include this in the
master build, if it fits.

- The minimum spindle PWM define in config.h needed to be update for
cpu map compatibilty.


----------------
Date: 2016-11-04
Author: Sonny Jeon
Subject: Fixed a g-code parser issue caused by last commit.

- G-code parser refactoring in the last commit wasn’t tested. Found and
fixed issues with G28.1/30.1 and G38.x probe commands. They were not
being accepted due to a borked mantissa check.


----------------
Date: 2016-11-04
Author: Sonny Jeon
Subject: Improved constant laser power per rate mode. Re-factored for flash size. Minor bug fixes.

- NOTE: This commit has largely been untested.

- Constant laser power per rate mode has been improved. Altered its
implementation to be more responsive and accurate.

- Based on LaserWeb dev feedback, only G1, G2, and G3 moves operate
with constant laser power mode. Meaning that G0, G38.x, and $J jogging
motions operate without it and will keep a constant power output. This
was specifically requested as a way to focus the laser by keeping the
laser on when not moving. Operationally, this shouldn’t alter how the
laser mode operates.

- Re-factored parts of the g-code parser and g-code state reports to
save a few hundred bytes of flash. What was done makes the code a bit
more unreadable (bad), but the flash space was in dire need. So, I’m
willing to live with it for now.

- Fixed a problem with $G g-code state reports. Showed `M0` program
pause during a run state. Now fixed to show nothing during a run state.
Also, `M30` program end was shown as `M2`. This was also corrected.

- Improved spindle stop override responsiveness by removing the
enforced spindle restoring delay. It’s not needed for a feature that is
user controlled.

- Fixed a bug with G2/3 arcs in inverse time mode.

- Updated the interface.md document to make it more clear how WPos: or
MPos: can be calculated from WCO:. Some GUI devs have failed to catch
this in the documentation.


----------------
Date: 2016-10-27
Author: Sonny Jeon
Subject: Spindle speed overrides behavior tweak. New experimental laser dynamic power mode.

- Spindle speed overrides now update immediately if they are changed
while in a HOLD state. Previously, they would update after exiting the
HOLD, which isn’t correct.

- New experimental dynamic laser power mode that adjusts laser power
based on current machine speed. Enabled by uncommenting
LASER_CONSTANT_POWER_PER_RATE in config.h

  - It assumes the programmed rate is the intended power/rate for the
motion.
  - Feed rate overrides (FRO) do not effect the power/rate. Meaning
that spindle PWM will automatically lower with lower FRO and increase
with higher FRO to keep it the same.
  - Spindle speed overrides (SSO) will directly increase and decrease
the power/rate. So 150% SSO will increase the PWM output by 150% for
the same speed.
  - The combination of FRO and SSO behaviors should allow for subtle
and highly flexible tuning of how the laser cutter is operating in
real-time and during the job.

- Re-factored planner block rapid rate handling for the dynamic laser
power feature. Should have had no effect on how Grbl operates.


----------------
Date: 2016-10-26
Author: Sonny Jeon
Subject: Add high-frequency spindle output option. Minor parking motion re-factoring.

- Some laser controllers were reported to need a very high PWM
frequency. Added a line to enable this in cpu_map.h, if needed.

- Cleaned up some of the parking code. Mostly just editing the comments.

- Moved the accessory state resetting after the initial parking
retract. Should ensure the accessory state is properly handled upon an
aborted parking restore. Not certain if this was a problem before
though. Just to be sure.


----------------
Date: 2016-10-25
Author: chamnit
Subject: Mandate all probe cycles ignore feed overrides.

- For repeatability reasons, all G38.x probe cycles ignore feed rate
overrides and move at their programmed speed.

- The mandate can be removed with a new config.h option.

- Updated the documentation to reflect the change.


----------------
Date: 2016-10-25
Author: chamnit
Subject: Resolved parking accessory handling issue.

- Yikes. Totally borked the last parking “fix”. Testing shows that all
accessories are now properly handled when retracting and restoring. It
was caused by not accounting for the planner re-factoring correctly in
the parking code.


----------------
Date: 2016-10-24
Author: Sonny Jeon
Subject: Minor re-factoring. Fix an issue with parking and spindle restore.

- Altered the report counters to be count down, rather than count up.
Simplified some of the logic.

- Fixed an issue with parking restore. The spindle state would disable
then reenable.

- Clarified some of the config.h descriptions.

- Moved the compile-time checks from config.h to grbl.h. They don’t
belong in the config.h file.

- Refactored the initialization of the system variables in main.c.
System position and probe position were undefined when power cycled,
but were zero anyway. Added clear vector code to make it explicit.


----------------
Date: 2016-10-23
Author: Sonny Jeon
Subject: Spindle speed close to minimum fix.

- When spindle speed is close to the minimum rpm, the PWM value would
be zero or lower than allowed. The computation error was caused by
setting the minimum PWM value to zero, when it should have been 1.

- Added a compiler check for minimum PWM to be greater than zero.

- Moved some of the spindle PWM macros to a more appropriate place in
the cpu_map.h.


----------------
Date: 2016-10-22
Author: Will Winder
Subject: Minor VARIABLE_SPINDLE feature toggle refactoring (#16)

* Modify code CSV format.

- Wrap value in quotes to avoid issue with embedded commas. This occurs
  in one of the alarm codes.

- Change header row format to allow same parsing code as data rows.

* VARIABLE_SPINDLE feature flag experiment.

- Use a macro for 'spindle_set_speed' and 'spindle_sync' to reduce the
  number of required VARIABLE_SPINDLE checks.


----------------
Date: 2016-10-18
Author: Sonny Jeon
Subject: Improved option for v0.9 GUI compatibility.

- Addressed an issue with backward compatibility with Grbl v0.9-style
GUIs.

- It still may not work due to new data and states coming back from
Grbl v1.1. Regardless, DO NOT TRY TO USE THE COMPATIBILITY MODE UNTIL
THERE IS A REALLY GOOD REASON TO.

- v0.9 GUI compatibility mode will be removed in future versions.
You’ve been warned. It’s highly recommended for GUIs to update to the
new v1.1 interface.

- Compability mode will only fit on an Arduino Uno due to size
increases.

- Removed the REPORT_GUI_MODE compile option since it’s part of the
v1.1 interface standard.

- Updated the documentation to better describe the compatibility mode
build option.


----------------
Date: 2016-10-17
Author: Sonny Jeon
Subject: 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


----------------
Date: 2016-10-17
Author: Will Winder
Subject: Modify code CSV format. (#10)

- Wrap value in quotes to avoid issue with embedded commas. This occurs
  in one of the alarm codes.

- Change header row format to allow same parsing code as data rows.

----------------
Date: 2016-10-12
Author: chamnit
Subject: Merge branch 'dev' into edge


----------------
Date: 2016-10-12
Author: chamnit
Subject: Added settings documentation. Very minor bug fix to step direction handling.

- Added v1.1 settings documentation to the markdown folder.

- Fixed a very minor bug in the step direction handling upon wakeup.
The direction mask would temporarily go back to default mask for about
a millisecond when moving in the same non-default direction. It did not
effect Grbl behavior before, but fixed for consistency.


----------------
Date: 2016-10-12
Author: Sonny Jeon
Subject: Spindle speed bug fix.

- Spindle speed updating wasn’t working in the g-code parser due to
some borked up logic on my part. Fixed it and should be operating as
intended for both normal and laser spindle modes.

- Elaborated a little more on the new sleep mode in the documentation.


----------------
Date: 2016-10-11
Author: Sonny Jeon
Subject: v1.1c: New sleep mode. Laser mode and other bug fixes.

- New $SLP sleep mode that will disable spindle, coolant, and stepper
enable pins. Allows users to disable their steppers without having to
alter their settings. A reset is required to exit and re-initializes in
alarm state.

- Laser mode wasn’t updating the spindle PWM correctly (effected
spindle speed overrides) and not checking for modal states either.
Fixed both issues.

- While in laser mode, parking motions are ignored, since the power off
delay with the retract motion would burn the material. It will just
turn off and not move. A restore immediately powers up and resumes. No
delays.

- Changing rpm max and min settings did not update the spindle PWM
calculations. Now fixed.

- Increased default planner buffer from 16 to 17 block. It seems to be
stable, but need to monitor this carefully.

- Removed software debounce routine for limit pins. Obsolete.

- Fixed a couple parking motion bugs. One related to restoring
incorrectly and the other the parking rate wasn’t compatible with the
planner structs.

- Fixed a bug caused by refactoring the critical alarms in a recent
push. Soft limits weren’t invoking a critical alarm.

- Updated the documentation with the new sleep feature and added some
more details to the change summary.


----------------
Date: 2016-09-28
Author: Sonny Jeon
Subject: New jog cancel real-time command. Parser typo fix from last push.

- Added a new jog cancel real-time command. Rather than depending on a
feed hold to cancel a jogging motion, this realtime command can be used
instead. The main advantage is if a feed hold is used, you can
accidentally hold the machine right when Grbl returns to IDLE after
completing a jog. And the GUI doesn’t have to worry about tracking this
either.

- Fixed a typo in the g-code parser edits from the last push. Was
causing the G10 set coordinate system command to not work correctly.

- Updated the documentation with the jog cancel command.


----------------
Date: 2016-09-27
Author: Sonny Jeon
Subject: Refactored g-code parser. Saved 60bytes flash and some ram. Edited Readme.

- Freed up another 60 bytes of flash and 12-24 bytes of stack RAM by
using the pre-allocated IJK arc offset vector that is guaranteed to be
not in use. Only G10 and G28/30 require fetching from EEPROM and
retaining extra data. Both commands use axis words, which rules out
G2/3 arcs using IJK offsets existing in same block. Not ideal, but
every byte helps.

- Edited README.


----------------
Date: 2016-09-27
Author: Sonny Jeon
Subject: Update README and clarifications in jogging document.


----------------
Date: 2016-09-26
Author: Sonny Jeon
Subject: v1.1b: Tweaked Bf reports, jogging doc, saved another 160 bytes, minor bug fixes

- Increment to v1.1b due to status report tweak.

- Tweaked the buffer state status reports to show bytes and blocks
available, rather than in use. This does not require knowing the buffer
sizes beforehand. It’s implicit.

- Also, since buffer states are not used by most devs (after
inquiries), it is no longer enabled by default and a status mask option
was added for this.

- Fixed some typos and updated for the report tweak in the
documentation.

- Wrote a joystick implementation concept in the jogging markdown
document. Outlines how to get a low-latency feel to a joystick (and
other input devices).

- Removed XON/XOFF support. It’s not used by anyone because of its
inherent problems. Remains in older versions for reference.

- Added a compile option on how to handle the probe position during a
check mode.

- Fixed a jogging bug. If G93 is the modal state before a jogging
motion, the feed rate did not get calculated correctly. Fixed the issue.

- Refactored some code to save another 160+ bytes. Included an improved
float vector comparison macro and reducing a few large and repetitive
function calls.

- Fixed a probing bug (existing in v0.9 too) where the target positions
were not set correct and error handling was improper.


----------------
Date: 2016-09-25
Author: Sonny Jeon
Subject: Addressed much larger flash size with avr-gcc v4.9.2. Refactored reports to save 160KB.

- The newest Arduino IDE 1.6.12 has recently updated to avr-gcc v4.9.2.
Unfortunately, it produces a compiled size almost 0.7KB to 1KB larger
than prior versions! This can easily cause the base build to exceed the
Arduino Duemilanove/Nano flash limit of 30.5KB. The Arduino Uno seems
to be ok still with its 31.5KB flash limit.

- Makefile `-flto` compile flag added to cut down on the horrible flash
size when using the new avr-gcc. (Edit Makefile and remove comment on
COMPILE definition). This brings it in-line with what the IDE produces.

- Functionalized repetitive tasks in report.c to try to reduce overall
flash size. Successfully cut down about 160bytes.

- Removed printFloat_SettingValue() and printFloat_RPMValue()
functions. These aren’t required and can be replaced with a direct call
to printFloat() because they don’t require a unit conversion check.


----------------
Date: 2016-09-24
Author: Sonny Jeon
Subject: Serial RX count bug fix. Settings codes CSV. More documentation.

- Reverted back the serial RX count function to how it was. The
variable type was unsigned and cause an integer underflow whenever the
calculation produced a negative number. The old way was the correct way.

- Lots of minor edits to the code CSVs and markdown documents.

- Expanded on explaining feedback messages and startup line execution
feedback.

- Created a new settings codes CSV to help GUIs import the values and
meanings.


----------------
Date: 2016-09-22
Author: Sonny Jeon
Subject: Increment to v1.1a, minor compile bug fix, tweaked communication protocol, more docs.

- Incremented to v1.1a, rather than keep 1.0e. This is because there
are existing v1.0 installations. Don’t want to confuse people further.

- Certain version of the Arduino IDE did not like the `inline` in the
function header. Removed from spindle_control files to fix the problem.

- Tweaked the communication protocol slightly. Added message type
indicators for all `[]`bracketed feedback messages. It’s been
problematic for GUI dev to try to determine the context of a message
and how it should be handled. These indictors should help tremendously
to remove context all together.

- Also altered how `$N` startup lines are presented when executed. They
now start with an open chevron ‘>’ followed by the line and an ‘:ok’ to
indicate it executed. The ‘ok’ is on the same line intentionally so it
doesn’t mess up a streaming protocol counter.

- Managed to save a 100+KB from refactoring parts of report.c. (Thanks
Vasilis!) Freed up room to alter the protocol a little.

- Wrote a markdown document on interface messaging to make it clear how
it’s intended to work. See interface.md in /doc/markdown

- Started to pull in some Wiki pages from the old grbl site and
beginning to update them for v1.1.

- Created new commit log for v1.1.


----------------
Date: 2016-09-22
Author: Sonny Jeon
Subject: Merge pull request #1 from winder/dev

Add locale to code CSVs.

----------------
Date: 2016-09-22
Author: winder
Subject: Add locale to code CSVs.


----------------
Date: 2016-09-21
Author: chamnit
Subject: Grbl v1.0e huge beta release. Overrides and new reporting.

- Feature: Realtime feed, rapid, and spindle speed overrides. These
alter the running machine state within tens of milliseconds!
    - Feed override: 100%, +/-10%, +/-1% commands with values 1-200% of
programmed feed
    - Rapid override: 100%, 50%, 25% rapid rate commands
    - Spindle speed override: 100%, +/-10%, +/-1% commands with values
50-200% of programmed speed
    - Override values have configurable limits and increments in
config.h.
- Feature: Realtime toggle overrides for spindle stop, flood coolant,
and optionally mist coolant
    - Spindle stop: Enables and disables spindle during a feed hold.
Automatically restores last spindles state.
    - Flood and mist coolant: Immediately toggles coolant state until
next toggle or g-code coolant command.
- Feature: Jogging mode! Incremental and absolute modes supported.
    - Grbl accepts jogging-specific commands like $J=X100F50. An axis
word and feed rate are required. G20/21 and G90/G91 commands are
accepted.
    - Jog motions can be canceled at any time by a feed hold `!`
command. The buffer is automatically flushed. (No resetting required).
    - Jog motions do not alter the g-code parser state so GUIs don’t
have to track what they changed and correct it.
- Feature: Laser mode setting. Allows Grbl to execute continuous
motions with spindle speed and state changes.
- Feature: Significantly improved status reports. Overhauled to cram in
more meaningful data and still make it smaller on average.
    - All available data is now sent by default, but does not appear if
it doesn’t change or is not active.
    - Machine position(MPos) or work position(WPos) is reported but not
both at the same time. Instead, the work coordinate offsets (WCO)are
sent intermittently whenever it changes or refreshes after 10-30 status
reports. Position vectors are easily computed by WPos  = MPos - WCO.
    - All data has changed in some way. Details of changes are in the
markdown documents and wiki.
- Feature: 16 new realtime commands to control overrides. All in
extended-ASCII character space.
    - While they are not easily typeable and requires a GUI, they can’t
be accidentally triggered by some latent character in the g-code
program and have tons of room for expansion.
- Feature: New substates for HOLD and SAFETY DOOR. A `:x` is appended
to the state, where `x` is an integer and indicates a substate.
    - For example, each integer of a door state describes in what phase
the machine is in during parking. Substates are detailed in the
documentation.
- Feature: With the alarm codes, homing and probe alarms have been
expanded with more codes to provide more exact feedback on what caused
the alarm.
- Feature: New hard limit check upon power-up or reset. If detected, a
feedback message to check the limit switches sent immediately after the
welcome message.
    - May be disabled in config.h.

- OEM feature: Enable/disable `$RST=` individual commands based on
desired behavior in config.h.
- OEM feature: Configurable EEPROM wipe to prevent certain data from
being deleted during firmware upgrade to a new settings version or
`RST=*` command.
- OEM feature: Enable/disable the `$I=` build info write string with
external EEPROM write example sketch.
    - This prevents a user from altering the build info string in
EEPROM. This requires the vendor to write the string to EEPROM via
external means. An Arduino example sketch is provided to accomplish
this. This would be useful for contain product data that is
retrievable.

- Tweak: All feedback has been drastically trimmed to free up flash
space for the v1.0 release.
    - The `$` help message is just one string, listing available
commands.
    - The `$$` settings printout no longer includes descriptions. Only
the setting values. (Sorry it’s this or remove overrides!)
    - Grbl `error:` and `ALARM:` responses now only contain codes. No
descriptions. All codes are explained in documentation.
    - Grbl’s old feedback style may be restored via a config.h, but
keep in mind that it will likely not fit into the Arduino’s flash space.
- Tweak: Grbl now forces a buffer sync or stop motion whenever a g-code
command needs to update and write a value to EEPROM or changes the work
coordinate offset.
    - This addresses two old issues in all prior Grbl versions. First,
an EEPROM write requires interrupts to be disabled, including stepper
and serial comm. Steps can be lost and data can be corrupted. Second,
the work position may not be correlated to the actual machine position,
since machine position is derived from the actual current execution
state, while work position is based on the g-code parser offset state.
They are usually not in sync and the parser state is several motions
behind. This forced sync ensures work and machine positions are always
correct.
    - This behavior can be disabled through a config.h option, but it’s
not recommended to do so.
- Tweak: To make status reports standardized, users can no longer
change what is reported via status report mask, except for only
toggling machine or work positions.
    - All other data fields are included in the report and can only be
disabled through the config.h file. It’s not recommended to alter this,
because GUIs will be expecting this data to be present and may not be
compatible.
- Tweak: Homing cycle and parking motion no longer report a negative
line number in a status report. These will now not report a line number
at all.
- Tweak: New `[Restoring spindle]` message when restoring from a
spindle stop override. Provides feedback what Grbl is doing while the
spindle is powering up and a 4.0 second delay is enforced.
- Tweak: Override values are reset to 100% upon M2/30. This behavior
can be disabled in config.h
- Tweak: The planner buffer size has been reduced from 18 to 16 to free
up RAM for tracking and controlling overrides.
- Tweak: TX buffer size has been increased from 64 to 90 bytes to
improve status reporting and overall performance.
- Tweak: Removed the MOTION CANCEL state. It was redundant and didn’t
affect Grbl’s overall operation by doing so.
- Tweak: Grbl’s serial buffer increased by +1 internally, such that 128
bytes means 128, not 127 due to the ring buffer implementation. Long
overdue.
- Tweak: Altered sys.alarm variable to be set by alarm codes, rather
than bit flags. Simplified how it worked overall.
- Tweak: Planner buffer and serial RX buffer usage has been combined in
the status reports.
- Tweak: Pin state reporting has been refactored to report only the
pins “triggered” and nothing when not “triggered”.
- Tweak: Current machine rate or speed is now included in every report.
- Tweak: The work coordinate offset (WCO) and override states only need
to be refreshed intermittently or reported when they change. The
refresh rates may be altered for each in the config.h file with
different idle and busy rates to lessen Grbl’s load during a job.
- Tweak: For temporary compatibility to existing GUIs until they are
updated, an option to revert back to the old style status reports is
available in config.h, but not recommended for long term use.
- Tweak: Removed old limit pin state reporting option from config.h in
lieu of new status report that includes them.
- Tweak: Updated the defaults.h file to include laser mode, altered
status report mask, and fix an issue with a missing invert probe pin
default.

- Refactor: Changed how planner line data is generated and passed to
the planner and onto the step generator. By making it a struct
variable, this saved significant flash space.
- Refactor: Major re-factoring of the planner to incorporate override
values and allow for re-calculations fast enough to immediately take
effect during operation. No small feat.
- Refactor: Re-factored the step segment generator for re-computing new
override states.
- Refactor: Re-factored spindle_control.c to accommodate the spindle
speed overrides and laser mode.
- Refactor: Re-factored parts of the codebase for a new jogging mode.
Still under development though and slated to be part of the official
v1.0 release. Hang tight.
- Refactor: Created functions for computing a unit vector and value
limiting based on axis maximums to free up more flash.
- Refactor: The spindle PWM is now set directly inside of the stepper
ISR as it loads new step segments.
- Refactor: Moved machine travel checks out of soft limits function
into its own since jogging uses this too.
- Refactor: Removed coolant_stop() and combined with
coolant_set_state().
- Refactor: The serial RX ISR forks off extended ASCII values to
quickly assess the new override realtime commands.
- Refactor: Altered some names of the step control flags.
- Refactor: Improved efficiency of the serial RX get buffer count
function.
- Refactor: Saved significant flash by removing and combining print
functions. Namely the uint8 base10 and base2 functions.
- Refactor: Moved the probe state check in the main stepper ISR to
improve its efficiency.
- Refactor: Single character printPgmStrings() went converted to direct
serial_write() commands to save significant flash space.

- Documentation: Detailed Markdown documents on error codes, alarm
codes, messages, new real-time commands, new status reports, and how
jogging works. More to come later and will be posted on the Wiki as
well.
- Documentation: CSV files for quick importing of Grbl error and alarm
codes.

- Bug Fix: Applied v0.9 master fixes to CoreXY homing.
- Bug Fix: The print float function would cause Grbl to crash if a
value was 1e6 or greater. Increased the buffer by 3 bytes to help
prevent this in the future.
- Bug Fix: Build info and startup string EEPROM restoring was not
writing the checksum value.
- Bug Fix: Corrected an issue with safety door restoring the proper
spindle and coolant state. It worked before, but breaks with laser mode
that can continually change spindle state per planner block.
- Bug Fix: Move system position and probe position arrays out of the
system_t struct. Ran into some compiling errors that were hard to track
down as to why. Moving them out fixed it.