- Completely overhauled the g-code parser. It’s now 100%* compliant. (*
may have some bugs). Being compliant, here are some of the major
differences.
- SMALLER and JUST AS FAST! A number of optimizations were found that
sped things up and allowed for the more thorough error-checking to be
installed without a speed hit. Trimmed a lot of ‘fat’ in the parser and
still was able to make it significantly smaller than it was.
- No default feed rate setting! Removed completely! This doesn’t exist
in the g-code standard. So, it now errors out whenever it’s undefined
for motions that require it (G1/2/3/38.2).
- Any g-code parser error expunges the ENTIRE block. This means all
information is lost and not passed on to the running state. Before some
of the states would remain, which could have led to some problems.
- If the g-code block passes all of the error-checks, the g-code state
is updated and all motions are executed according to the order of
execution.
- Changes in spindle speed, when already running, will update the
output pin accordingly. This fixes a bug, where it wouldn’t update the
speed.
- Update g-code parser error reporting. Errors now return detailed
information of what exact went wrong. The most common errors return a
short text description. For less common errors, the parser reports
‘Invalid gcode ID:20’, where 20 is a error ID. A list of error code IDs
and their descriptions will be documented for user reference elsewhere
to save flash space.
- Other notable changes:
- Added a print integer routine for uint8 variables. This saved
significant flash space by switching from a heavier universal print
integer routine.
- Saved some flash space with our own short hypotenuse calculation
- Some arc computation flash and memory optimizations.
- Added a new source and header file called system. These files contain
the system commands and variables, as well as all of the system headers
and standard libraries Grbl uses. Centralizing some of the code.
- Re-organized the include headers throughout the source code.
- ENABLE_M7 define was missing from config.h. Now there.
- SPINDLE_MAX_RPM and SPINDLE_MIN_RPM now defined in config.h. No
uncommenting to prevent user issues. Minimum spindle RPM now provides
the lower, near 0V, scale adjustment, i.e. some spindles can go really
slow so why use up our 256 voltage bins for them?
- Remove some persistent variables from coolant and spindle control.
They were redundant.
- Removed a VARIABLE_SPINDLE define in cpu_map.h that shouldn’t have
been there.
- Changed the DEFAULT_ARC_TOLERANCE to 0.002mm to improve arc tracing.
Before we had issues with performance, no longer.
- Fixed a bug with the hard limits and the software debounce feature
enabled. The invert limit pin setting wasn’t honored.
- Fixed a bug with the homing direction mask. Now is like it used to
be. At least for now.
- Re-organized main.c to serve as only as the reset/initialization
routine. Makes things a little bit clearer in terms of execution
procedures.
- Re-organized protocol.c as the overall master control unit for
execution procedures. Not quite there yet, but starting to make a
little more sense in how things are run.
- Removed updating of old settings records. So many new settings have
been added that it’s not worth adding the code to migrate old user
settings.
- Tweaked spindle_control.c a bit and made it more clear and consistent
with other parts of Grbl.
- Tweaked the stepper disable bit code in stepper.c. Requires less
flash memory.
- Homing travel calculations fixed. It was computing the min travel
rather than max.
- Auto-start disable and pausing after spindle or dwell commands.
Related to plan_synchronize() function call. Now fixed, but still need
to work on the system state.
- Pushed a fix to make this branch more Arduino IDE compatible. Removed
extern call in nuts_bolts.c
- Updated the stepper configuration option of enabling or disabling the
new Adaptive Multi-Axis Step Smoothing Algorithm. Now works either way.
- Updated some copyright info.
- NEW! An active multi-axis step smoothing algorithm that automatically
adjusts dependent on step frequency. This solves the long standing
issue to aliasing when moving with multiple axes. Similar in scheme to
Smoothieware, but more advanced in ensuring a more consistent CPU
overhead throughout all frequencies while maintaining step exactness.
- Switched from Timer2 to Timer0 for the Step Port Reset Interrupt.
Mainly to free up hardware PWM pins.
- Seperated the direction and step pin assignments, so we can now move
them to seperate ports. This means that we can more easily support 4+
axes in the future.
- Added a setting for inverting the limit pins, as so many users have
request. Better late than never.
- Bug fix related to EEPROM calls when in cycle. The EEPROM would kill
the stepper motion. Now protocol mandates that the system be either in
IDLE or ALARM to access or change any settings.
- Bug fix related to resuming the cycle after a spindle or dwell
command if auto start has been disabled. This fix is somewhat temporary
or more of a patch. Doesn’t work with a straight call-response
streaming protocol, but works fine with serial buffer pre-filling
streaming that most clients use.
- Renamed the pin_map.h to cpu_map.h to more accurately describe what
the file is.
- Pushed an auto start bug fix upon re-initialization.
- Much more polishing to do!
- Revamped and improved homing cycle. Now tied directly into the main
planner and stepper code, which enables much faster homing seek rates.
Also dropped the compiled flash size by almost 1KB, meaning 1KB more
for other features.
- Refactored config.h. Removed obsolete defines and configuration
options. Moved lots of “advanced” options into the advanced area of the
file.
- Updated defaults.h with the new homing cycle. Also updated the
Sherline 5400 defaults and added the ShapeOko2 defaults per user
submissions.
- Fixed a bug where the individual axes limits on velocity and
acceleration were not working correctly. Caused by abs() returning a
int, rather than a float. Corrected with fabs(). Duh.
- Added build version/date to the Grbl welcome message to help indicate
which version a user is operating on.
- Max travel settings were not being defaulted into the settings EEPROM
correctly. Fixed.
- To stop a single axis during a multi-axes homing move, the stepper
algorithm now has a simple axis lock mask which inhibits the desired
axes from moving. Meaning, if one of the limit switches engages before
the other, we stop that one axes and keep moving the other.
- A minor issue with deceleration ramps when close to zero velocity.
Should be virtually unnoticeable for most CNC systems, but fixed in
this push and accurate to physics.
- Updated some of the junction deviation defaults. Because the new
stepper algorithm can easily maximize a CNC machine’s capabilities or
simply go much faster, this means the speed in which it enters
junctions has to be a little more constrained. Meaning that, we have to
slow a little bit down more so that we don’t exceed the acceleration
limits of the stepper motors.
- Pushed limit switch active high option (i.e. NC switches).
- Updated defaults.h to be in-line with the new settings.
- Refactored feed hold handling and step segment buffer to be more
generalized in effort to make adding feedrate overrides easier in the
future. Also made it a little more clean.
- Fixed G18 plane select issue. Now ZX-plane, rather than XZ-plane, per
right hand rule.
- Cleaned some of the system settings by more accurately renaming some
of the variables and removing old obsolete ones.
- Declared serial.c rx_buffer_tail to be volatile. No effect, since
avr-gcc automatically does this during compilation. Helps with porting
when using other compilers.
- Updated version number to v0.9b.
- Updates to README.md
- Arc mm_per_segment parameter was removed and replaced with an
arc_tolerance parameter, which scales all arc segments automatically to
radius, such that the line segment error doesn't exceed the tolerance.
Significantly improves arc performance through larger radius arc,
because the segments are much longer and the planner buffer has more to
work with.
- Moved n_arc correction from the settings to config.h. Mathematically
this doesn't need to be a setting anymore, as the default config value
will work for all known CNC applications. The error does not accumulate
as much anymore, since the small angle approximation used by the arc
generation has been updated to a third-order approximation and how the
line segment length scale with radius and tolerance now. Left in
config.h for extraneous circumstances.
- Corrected the st.ramp_count variable (acceleration tick counter) to a
8-bit vs. 32-bit variable. Should make the stepper algorithm just a
touch faster overall.
- Planner execute speed has been more than halved from 4ms to 1.9ms
when computing a plan for a single line segment during arc generation.
This means that Grbl can now run through an arc (or complex curve)
twice as fast as before without starving the buffer. For 0.1mm arc
segments, this means about the theoretical feed rate limit is about
3000mm/min for arcs now.
- Increased the Ranade timer frequency to 30kHz, as there doesn't seem
to be any problems with increasing the frequency. This means that the
maximum step frequency is now back at 30kHz.
- Added Zen Toolworks 7x7 defaults.
- Brand-new stepper algorithm. Based on the Pramod Ranade inverse time
algorithm, but modified to ensure step events are exact. Currently
limited to about 15kHz step rates, much more to be done to enable 30kHz
again.
- Removed Timer1. Stepper algorithm now uses Timer0 and Timer2.
- Much improved step generation during accelerations. Smoother. Allows
much higher accelerations (and speeds) than before on the same machine.
- Cleaner algorithm that is more easily portable to other CPU types.
- Streamlined planner calculations. Removed accelerate_until and
final_rate variables from block buffer since the new stepper algorithm
is that much more accurate.
- Improved planner efficiency by about 15-20% during worst case
scenarios (arcs).
- New config.h options to tune new stepper algorithm.
- Updated interface protocol to play nicer with interface programs. All
Grbl responses beginning with '$' signifies a setting. Bracketed '[]'
responses are feedback messages containing either state, parameter, or
general messages. Chevron '<>' response are from the real-time status
messages, i.e. position.
- M2 Program end command was causing a system alarm. Fixed. Thanks
@blinkenlight !
- The homing sequence is now a compile-time option, where a user can
choose which axes(s) move in sequence during the search phase. Up to 3
sequences. Works with the locating phase and the pull-off maneuver.
- New defaults.h file to store user generated default settings for
different machines. Mainly to be used as a central repo, but each set
may be select to be compiled in as a config.h define.
Sonny Jeon