Syncing mainstream v1.1f

- See details in mainstream commits from 1/14/17 to 7/17/17.
grbl · ondabeach · Aug 28, 2015 · Aug 28, 2015 · Aug 29, 2015 · Sep 5, 2015
commit 4b8e411ca756a3b6ad089d08d3b87056d01bad2d
diff --git a/README.md b/README.md
@@ -1,6 +1,6 @@
 ![GitHub Logo](https://github.com/gnea/gnea-Media/blob/master/Grbl%20Logo/Grbl%20Logo%20250px.png?raw=true)
 ***
-_Click the `Release` tab to download pre-compiled `.hex` files or just [click here](https://github.com/gnea/grbl/releases)_
+_Click the `Release` tab to download pre-compiled `.hex` files or just [click here](https://github.com/gnea/grbl-Mega/releases)_
 ***
 
 Grbl is a no-compromise, high performance, low cost alternative to parallel-port-based motion control for CNC milling. This version of Grbl runs on an Arduino Mega2560 only.

diff --git a/doc/csv/build_option_codes_en_US.csv b/doc/csv/build_option_codes_en_US.csv
@@ -6,11 +6,16 @@
 "P","Parking motion","Enabled"
 "Z","Homing force origin","Enabled"
 "H","Homing single axis commands","Enabled"
-"L","Two limit switches on axis","Enabled"
+"T","Two limit switches on axis","Enabled"
 "A","Allow feed rate overrides in probe cycles","Enabled"
+"D","Use spindle direction as enable pin","Enabled"
+"0","Spindle enable off when speed is zero","Enabled"
+"S","Software limit pin debouncing","Enabled"
+"R","Parking override control","Enabled"
 "*","Restore all EEPROM command","Disabled"
 "$","Restore EEPROM `$` settings command","Disabled"
 "#","Restore EEPROM parameter data command","Disabled"
 "I","Build info write user string command","Disabled"
 "E","Force sync upon EEPROM write","Disabled"
-"W","Force sync upon work coordinate offset change","Disabled"
+"W","Force sync upon work coordinate offset change","Disabled"
+"L","Homing initialization auto-lock","Disabled"
diff --git a/doc/csv/error_codes_en_US.csv b/doc/csv/error_codes_en_US.csv
@@ -1,36 +1,37 @@
-Error Code in v1.1+ ,Error Message in v1.0-, Error Description
-1,Expected command letter,G-code words consist of a letter and a value. Letter was not found.
-2,Bad number format,Missing the expected G-code word value or numeric value format is not valid.
-3,Invalid statement,Grbl '$' system command was not recognized or supported.
-4,Value < 0,Negative value received for an expected positive value.
-5,Setting disabled,Homing cycle failure. Homing is not enabled via settings.
-6,Value < 3 usec,Minimum step pulse time must be greater than 3usec.
-7,EEPROM read fail. Using defaults,An EEPROM read failed. Auto-restoring affected EEPROM to default values.
-8,Not idle,Grbl '$' command cannot be used unless Grbl is IDLE. Ensures smooth operation during a job.
-9,G-code lock,G-code commands are locked out during alarm or jog state.
-10,Homing not enabled,Soft limits cannot be enabled without homing also enabled.
-11,Line overflow,Max characters per line exceeded. Received command line was not executed.
-12,Step rate > 30kHz,Grbl '$' setting value cause the step rate to exceed the maximum supported.
-13,Check Door,Safety door detected as opened and door state initiated.
-14,Line length exceeded,Build info or startup line exceeded EEPROM line length limit. Line not stored.
-15,Travel exceeded,Jog target exceeds machine travel. Jog command has been ignored.
-16,Invalid jog command,Jog command has no '=' or contains prohibited g-code.
-20,Unsupported command,Unsupported or invalid g-code command found in block.
-21,Modal group violation,More than one g-code command from same modal group found in block.
-22,Undefined feed rate,Feed rate has not yet been set or is undefined.
-23,Invalid gcode ID:23,G-code command in block requires an integer value.
-24,Invalid gcode ID:24,More than one g-code command that requires axis words found in block.
-25,Invalid gcode ID:25,Repeated g-code word found in block.
-26,Invalid gcode ID:26,No axis words found in block for g-code command or current modal state which requires them.
-27,Invalid gcode ID:27,Line number value is invalid.
-28,Invalid gcode ID:28,G-code command is missing a required value word.
-29,Invalid gcode ID:29,G59.x work coordinate systems are not supported.
-30,Invalid gcode ID:30,G53 only allowed with G0 and G1 motion modes.
-31,Invalid gcode ID:31,Axis words found in block when no command or current modal state uses them.
-32,Invalid gcode ID:32,G2 and G3 arcs require at least one in-plane axis word.
-33,Invalid gcode ID:33,Motion command target is invalid.
-34,Invalid gcode ID:34,Arc radius value is invalid.
-35,Invalid gcode ID:35,G2 and G3 arcs require at least one in-plane offset word.
-36,Invalid gcode ID:36,Unused value words found in block.
-37,Invalid gcode ID:37,G43.1 dynamic tool length offset is not assigned to configured tool length axis.
-38,Invalid gcode ID:38,Tool number greater than max supported value.
+"Error Code in v1.1+","Error Message in v1.0-","Error Description"
+"1","Expected command letter","G-code words consist of a letter and a value. Letter was not found."
+"2","Bad number format","Missing the expected G-code word value or numeric value format is not valid."
+"3","Invalid statement","Grbl '$' system command was not recognized or supported."
+"4","Value < 0","Negative value received for an expected positive value."
+"5","Setting disabled","Homing cycle failure. Homing is not enabled via settings."
+"6","Value < 3 usec","Minimum step pulse time must be greater than 3usec."
+"7","EEPROM read fail. Using defaults","An EEPROM read failed. Auto-restoring affected EEPROM to default values."
+"8","Not idle","Grbl '$' command cannot be used unless Grbl is IDLE. Ensures smooth operation during a job."
+"9","G-code lock","G-code commands are locked out during alarm or jog state."
+"10","Homing not enabled","Soft limits cannot be enabled without homing also enabled."
+"11","Line overflow","Max characters per line exceeded. Received command line was not executed."
+"12","Step rate > 30kHz","Grbl '$' setting value cause the step rate to exceed the maximum supported."
+"13","Check Door","Safety door detected as opened and door state initiated."
+"14","Line length exceeded","Build info or startup line exceeded EEPROM line length limit. Line not stored."
+"15","Travel exceeded","Jog target exceeds machine travel. Jog command has been ignored."
+"16","Invalid jog command","Jog command has no '=' or contains prohibited g-code."
+"17","Setting disabled","Laser mode requires PWM output."
+"20","Unsupported command","Unsupported or invalid g-code command found in block."
+"21","Modal group violation","More than one g-code command from same modal group found in block."
+"22","Undefined feed rate","Feed rate has not yet been set or is undefined."
+"23","Invalid gcode ID:23","G-code command in block requires an integer value."
+"24","Invalid gcode ID:24","More than one g-code command that requires axis words found in block."
+"25","Invalid gcode ID:25","Repeated g-code word found in block."
+"26","Invalid gcode ID:26","No axis words found in block for g-code command or current modal state which requires them."
+"27","Invalid gcode ID:27","Line number value is invalid."
+"28","Invalid gcode ID:28","G-code command is missing a required value word."
+"29","Invalid gcode ID:29","G59.x work coordinate systems are not supported."
+"30","Invalid gcode ID:30","G53 only allowed with G0 and G1 motion modes."
+"31","Invalid gcode ID:31","Axis words found in block when no command or current modal state uses them."
+"32","Invalid gcode ID:32","G2 and G3 arcs require at least one in-plane axis word."
+"33","Invalid gcode ID:33","Motion command target is invalid."
+"34","Invalid gcode ID:34","Arc radius value is invalid."
+"35","Invalid gcode ID:35","G2 and G3 arcs require at least one in-plane offset word."
+"36","Invalid gcode ID:36","Unused value words found in block."
+"37","Invalid gcode ID:37","G43.1 dynamic tool length offset is not assigned to configured tool length axis."
+"38","Invalid gcode ID:38","Tool number greater than max supported value."
diff --git a/doc/markdown/change_summary.md b/doc/markdown/change_summary.md
@@ -109,4 +109,6 @@ On a final note, these interface tweaks came about out of necessity, because mor
 - 	`$J=line` New jogging commands. This command behaves much like a normal G1 command, but there are some key differences. Jog commands don't alter the g-code parser state, meaning a GUI doesn't have to manage it anymore. Jog commands may be queued and cancelled at any time, where they are automatically flushed from the planner buffer without requiring a reset. See the jogging documentation on how they work and how they may be used to implement a low-latency joystick or rotary dial.
 
 - Laser mode `$` setting - When enabled, laser mode will move through consecutive G1, G2, and G3 motion commands that have different spindle speed values without stopping. A spindle speed of zero will disable the laser without stopping as well. However, when spindle states change, like M3 or M5, stops are still enforced.
-	- NOTE: Parking motions are automatically disabled when laser mode is enabled to prevent burning.
+	- NOTE: Parking motions are automatically disabled when laser mode is enabled to prevent burning.
+
+- `G56 P1` and `G56 P0` - When enabled in config.h with Grbl's parking motion, these commands enable and disable, respectively, the parking motion. Like all override control commands, these commands are modal and are part of the g-code stream.
diff --git a/doc/markdown/commands.md b/doc/markdown/commands.md
@@ -64,7 +64,7 @@ This command prints all of the active gcode modes in Grbl's G-code parser. When
 
 These active modes determine how the next G-code block or command will be interpreted by Grbl's G-code parser. For those new to G-code and CNC machining, modes sets the parser into a particular state so you don't have to constantly tell the parser how to parse it. These modes are organized into sets called "modal groups" that cannot be logically active at the same time. For example, the units modal group sets whether your G-code program is interpreted in inches or in millimeters.
 
-A short list of the modal groups, supported by Grbl, is shown below, but more complete and detailed descriptions can be found at LinuxCNC's [website](http://www.linuxcnc.org/docs/2.4/html/gcode_overview.html#sec:Modal-Groups). The G-code commands in **bold** indicate the default modes upon powering-up Grbl or resetting it.
+A short list of the modal groups, supported by Grbl, is shown below, but more complete and detailed descriptions can be found at LinuxCNC's [website](http://www.linuxcnc.org/docs/2.4/html/gcode_overview.html#sec:Modal-Groups). The G-code commands in **bold** indicate the default modes upon powering-up Grbl or resetting it. The commands in _italics_ indicate a special Grbl-only command.
 
 | Modal Group Meaning	|  Member Words |
 |:----:|:----:|
@@ -80,6 +80,9 @@ A short list of the modal groups, supported by Grbl, is shown below, but more co
 |Program Mode | **M0**, M1, M2, M30|
 |Spindle State |M3, M4, **M5**|
 |Coolant State	| M7, M8, **M9** |
+|Override Control | _M56_ |
+
+Grbl supports a special _M56_ override control command, where this enables and disables Grbl's parking motion when a `P1` or a `P0` is passed with `M56`, respectively. This command is only available when both parking and this particular option is enabled.
 
 In addition to the G-code parser modes, Grbl will report the active `T` tool number, `S` spindle speed, and `F` feed rate, which all default to 0 upon a reset. For those that are curious, these don't quite fit into nice modal groups, but are just as important for determining the parser state.
 

diff --git a/doc/markdown/interface.md b/doc/markdown/interface.md
@@ -62,11 +62,9 @@ The real-time control commands, `~` cycle start/resume, `!` feed hold,  `^X` sof
 One important note are the override command characters. These are defined in the extended-ASCII character space and are generally not type-able on a keyboard. A GUI must be able to send these 8-bit values to support overrides. 
 
 #### EEPROM Issues
-EEPROM access on the Arduino AVR CPUs turns off all of the interrupts while the CPU reads and writes to EEPROM. This poses a problem for certain features in Grbl, particularly if a user is streaming and running a g-code program, since it can pause the main step generator interrupt from executing on time. Most of the EEPROM access is restricted by Grbl when it's in certain states, but there are some things that developers need to know.
+EEPROM access on the Arduino AVR CPUs turns off all of the interrupts while the CPU _writes_ to EEPROM. This poses a problem for certain features in Grbl, particularly if a user is streaming and running a g-code program, since it can pause the main step generator interrupt from executing on time. Most of the EEPROM access is restricted by Grbl when it's in certain states, but there are some things that developers need to know.
 
-* Settings should not be streamed with the character-counting streaming protocols. Only the simple send-response protocol works. This is because during the EEPROM write, the AVR CPU also shuts-down the serial RX interrupt, which means data can get corrupted or lost.
-
-* When changing work coordinates or accessing the `G28`/`G30` predefined positions, Grbl has to fetch them from EEPROM. There is a small chance this access can pause the stepper or serial receive interrupt long enough to cause motion issues, but since it only fetches 12 bytes at a time at 2 cycles per fetch, the chances are very small that this will do anything to how Grbl runs. We just suggest keeping an eye on this and report to us any issues you might think are related to this.
+* Settings should not be streamed with the character-counting streaming protocols. Only the simple send-response protocol works. This is because during the EEPROM write, the AVR CPU also shuts-down the serial RX interrupt, which means data can get corrupted or lost. This is safe with the send-response protocol, because it's not sending data after commanding Grbl to save data.
 
 For reference:
 * Grbl's EEPROM write commands: `G10 L2`, `G10 L20`, `G28.1`, `G30.1`, `$x=`, `$I=`, `$Nx=`, `$RST=`
@@ -156,6 +154,7 @@ Every G-code block sent to Grbl and Grbl `$` system command that is terminated w
 | **`14`** | (Grbl-Mega Only) Build info or startup line exceeded EEPROM line length limit. |
 | **`15`** | Jog target exceeds machine travel. Command ignored. |
 | **`16`** | Jog command with no '=' or contains prohibited g-code. |
+| **`17`** | Laser mode disabled. Requires PWM output. |
 | **`20`** | Unsupported or invalid g-code command found in block. |
 | **`21`** | More than one g-code command from same modal group found in block.|
 | **`22`** | Feed rate has not yet been set or is undefined. |
@@ -410,16 +409,16 @@ Feedback messages provide non-critical information on what Grbl is doing, what i
   - `[VER:]` and `[OPT:]`: Indicates build info data from a `$I` user query. These build info messages are followed by an `ok` to confirm the `$I` was executed, like so:
 
       ```
-      [VER:v1.1d.20161014:Some string]
-      [OPT:VL]
+      [VER:v1.1f.20170131:Some string]
+      [OPT:VL,16,128]
       ok
       ```
 
   		- The first line `[VER:]` contains the build version and date.
       - A string may appear after the second `:` colon. It is a stored EEPROM string a user via a `$I=line` command or OEM can place there for personal use or tracking purposes.
-  		- The `[OPT:]` line follows immediately after and contains character codes for compile-time options that were either enabled or disabled. The codes are defined below and a CSV file is also provided for quick parsing. This is generally only used for quickly diagnosing firmware bugs or compatibility issues.
+  		- The `[OPT:]` line follows immediately after and contains character codes for compile-time options that were either enabled or disabled and two values separated by commas, which indicates the total usable planner blocks and serial RX buffer bytes, respectively. The codes are defined below and a CSV file is also provided for quick parsing. This is generally only used for quickly diagnosing firmware bugs or compatibility issues. 
 
-		| `OPT` Code | Setting Description, Units |
+			| `OPT` Code | Setting Description, Units |
 |:-------------:|----|
 | **`V`** | Variable spindle enabled |
 | **`N`** | Line numbers enabled |
@@ -428,15 +427,20 @@ Feedback messages provide non-critical information on what Grbl is doing, what i
 | **`P`** | Parking motion enabled |
 | **`Z`** | Homing force origin enabled |
 | **`H`** | Homing single axis enabled |
-| **`L`** | Two limit switches on axis enabled |
+| **`T`** | Two limit switches on axis enabled |
+| **`D`** | Spindle direction pin used as enable pin |
+| **`0`** | Spindle enable off when speed is zero enabled |
+| **`S`** | Software limit pin debouncing enabled |
+| **`R`** | Parking override control enabled |
 | **`A`** | Allow feed rate overrides in probe cycles |
 | **`*`** | Restore all EEPROM disabled |
 | **`$`** | Restore EEPROM `$` settings disabled |
 | **`#`** | Restore EEPROM parameter data disabled |
 | **`I`** | Build info write user string disabled |
 | **`E`** | Force sync upon EEPROM write disabled |
 | **`W`** | Force sync upon work coordinate offset change disabled |
-
+| **`L`** | Homing initialization auto-lock disabled |
+
   - `[echo:]` : Indicates an automated line echo from a command just prior to being parsed and executed. May be enabled only by a config.h option. Often used for debugging communication issues. A typical line echo message is shown below. A separate `ok` will eventually appear to confirm the line has been parsed and executed, but may not be immediate as with any line command containing motions.
       ```
       [echo:G1X0.540Y10.4F100]