Sergey Pastor / grbl_1_

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doc/markdown/commands.md@0:9dcf85d9b2f3, 2017-09-04 (annotated)

Committer:
Sergunb
Date:
Mon Sep 04 12:05:05 2017 +0000
Revision:
0:9dcf85d9b2f3
Initial commit

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Sergunb 0:9dcf85d9b2f3 1 # Grbl v1.1 Commands
Sergunb 0:9dcf85d9b2f3 2
Sergunb 0:9dcf85d9b2f3 3 In general, Grbl assumes all characters and streaming data sent to it is g-code and will parse and try to execute it as soon as it can. However, Grbl also has two separate system command types that are outside of the normal g-code streaming. One system command type is streamed to Grbl like g-code, but starts with a `$` character to tell Grbl it's not g-code. The other is composed of a special set of characters that will immediately command Grbl to do a task in real-time. It's not part of the g-code stream. Grbl's system commands do things like control machine state, report saved parameters or what Grbl is doing, save or print machine settings, run a homing cycle, or make the machine move faster or slower than programmed. This document describes these "internal" system Grbl commands, what they do, how they work, and how to use them.
Sergunb 0:9dcf85d9b2f3 4
Sergunb 0:9dcf85d9b2f3 5 ## Getting Started
Sergunb 0:9dcf85d9b2f3 6
Sergunb 0:9dcf85d9b2f3 7 First, connect to Grbl using the serial terminal of your choice.
Sergunb 0:9dcf85d9b2f3 8
Sergunb 0:9dcf85d9b2f3 9 Set the baud rate to **115200** as 8-N-1 (8-bits, no parity, and 1-stop bit.)
Sergunb 0:9dcf85d9b2f3 10
Sergunb 0:9dcf85d9b2f3 11 Once connected
Sergunb 0:9dcf85d9b2f3 12 you should get the Grbl-prompt, which looks like this:
Sergunb 0:9dcf85d9b2f3 13
Sergunb 0:9dcf85d9b2f3 14 ```
Sergunb 0:9dcf85d9b2f3 15 Grbl 1.1e ['$' for help]
Sergunb 0:9dcf85d9b2f3 16 ```
Sergunb 0:9dcf85d9b2f3 17
Sergunb 0:9dcf85d9b2f3 18 Type $ and press enter to have Grbl print a help message. You should not see any local echo of the $ and enter. Grbl should respond with:
Sergunb 0:9dcf85d9b2f3 19
Sergunb 0:9dcf85d9b2f3 20 ```
Sergunb 0:9dcf85d9b2f3 21 [HLP:$$ $# $G $I $N $x=val $Nx=line $J=line $SLP $C $X $H ~ ! ? ctrl-x]
Sergunb 0:9dcf85d9b2f3 22 ```
Sergunb 0:9dcf85d9b2f3 23
Sergunb 0:9dcf85d9b2f3 24 The ‘$’-commands are Grbl system commands used to tweak the settings, view or change Grbl's states and running modes, and start a homing cycle. The last four **non**-'$' commands are realtime control commands that can be sent at anytime, no matter what Grbl is doing. These either immediately change Grbl's running behavior or immediately print a report of the important realtime data like current position (aka DRO). There are over a dozen more realtime control commands, but they are not user type-able. See realtime command section for details.
Sergunb 0:9dcf85d9b2f3 25
Sergunb 0:9dcf85d9b2f3 26 ***
Sergunb 0:9dcf85d9b2f3 27
Sergunb 0:9dcf85d9b2f3 28 ## Grbl '$' Commands
Sergunb 0:9dcf85d9b2f3 29
Sergunb 0:9dcf85d9b2f3 30 The `$` system commands provide additional controls for the user, such as printing feedback on the current G-code parser modal state or running the homing cycle. This section explains what these commands are and how to use them.
Sergunb 0:9dcf85d9b2f3 31
Sergunb 0:9dcf85d9b2f3 32 #### `$$`and `$x=val` - View and write Grbl settings
Sergunb 0:9dcf85d9b2f3 33 See [Grbl v1.1 Configuration](https://github.com/gnea/grbl/wiki/Grbl-v1.1-Configuration#grbl-settings) for more details on how to view and write setting and learn what they are.
Sergunb 0:9dcf85d9b2f3 34
Sergunb 0:9dcf85d9b2f3 35 #### `$#` - View gcode parameters
Sergunb 0:9dcf85d9b2f3 36
Sergunb 0:9dcf85d9b2f3 37 G-code parameters store the coordinate offset values for G54-G59 work coordinates, G28/G30 pre-defined positions, G92 coordinate offset, tool length offsets, and probing (not officially, but we added here anyway). Most of these parameters are directly written to EEPROM anytime they are changed and are persistent. Meaning that they will remain the same, regardless of power-down, until they are explicitly changed. The non-persistent parameters, which will are not retained when reset or power-cycled, are G92, G43.1 tool length offsets, and the G38.2 probing data.
Sergunb 0:9dcf85d9b2f3 38
Sergunb 0:9dcf85d9b2f3 39 G54-G59 work coordinates can be changed via the `G10 L2 Px` or `G10 L20 Px` command defined by the NIST gcode standard and the EMC2 (linuxcnc.org) standard. G28/G30 pre-defined positions can be changed via the `G28.1` and the `G30.1` commands, respectively.
Sergunb 0:9dcf85d9b2f3 40
Sergunb 0:9dcf85d9b2f3 41 When `$#` is called, Grbl will respond with the stored offsets from machine coordinates for each system as follows. `TLO` denotes tool length offset (for the default z-axis), and `PRB` denotes the coordinates of the last probing cycle, where the suffix `:1` denotes if the last probe was successful and `:0` as not successful.
Sergunb 0:9dcf85d9b2f3 42
Sergunb 0:9dcf85d9b2f3 43 ```
Sergunb 0:9dcf85d9b2f3 44 [G54:4.000,0.000,0.000]
Sergunb 0:9dcf85d9b2f3 45 [G55:4.000,6.000,7.000]
Sergunb 0:9dcf85d9b2f3 46 [G56:0.000,0.000,0.000]
Sergunb 0:9dcf85d9b2f3 47 [G57:0.000,0.000,0.000]
Sergunb 0:9dcf85d9b2f3 48 [G58:0.000,0.000,0.000]
Sergunb 0:9dcf85d9b2f3 49 [G59:0.000,0.000,0.000]
Sergunb 0:9dcf85d9b2f3 50 [G28:1.000,2.000,0.000]
Sergunb 0:9dcf85d9b2f3 51 [G30:4.000,6.000,0.000]
Sergunb 0:9dcf85d9b2f3 52 [G92:0.000,0.000,0.000]
Sergunb 0:9dcf85d9b2f3 53 [TLO:0.000]
Sergunb 0:9dcf85d9b2f3 54 [PRB:0.000,0.000,0.000:0]
Sergunb 0:9dcf85d9b2f3 55 ```
Sergunb 0:9dcf85d9b2f3 56
Sergunb 0:9dcf85d9b2f3 57 #### `$G` - View gcode parser state
Sergunb 0:9dcf85d9b2f3 58
Sergunb 0:9dcf85d9b2f3 59 This command prints all of the active gcode modes in Grbl's G-code parser. When sending this command to Grbl, it will reply with a message starting with an `[GC:` indicator like:
Sergunb 0:9dcf85d9b2f3 60
Sergunb 0:9dcf85d9b2f3 61 ```
Sergunb 0:9dcf85d9b2f3 62 [GC:G0 G54 G17 G21 G90 G94 M0 M5 M9 T0 S0.0 F500.0]
Sergunb 0:9dcf85d9b2f3 63 ```
Sergunb 0:9dcf85d9b2f3 64
Sergunb 0:9dcf85d9b2f3 65 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.
Sergunb 0:9dcf85d9b2f3 66
Sergunb 0:9dcf85d9b2f3 67 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.
Sergunb 0:9dcf85d9b2f3 68
Sergunb 0:9dcf85d9b2f3 69 | Modal Group Meaning | Member Words |
Sergunb 0:9dcf85d9b2f3 70 |:----:|:----:|
Sergunb 0:9dcf85d9b2f3 71 | Motion Mode | **G0**, G1, G2, G3, G38.2, G38.3, G38.4, G38.5, G80 |
Sergunb 0:9dcf85d9b2f3 72 |Coordinate System Select | **G54**, G55, G56, G57, G58, G59|
Sergunb 0:9dcf85d9b2f3 73 |Plane Select | **G17**, G18, G19|
Sergunb 0:9dcf85d9b2f3 74 |Distance Mode | **G90**, G91|
Sergunb 0:9dcf85d9b2f3 75 |Arc IJK Distance Mode | **G91.1** |
Sergunb 0:9dcf85d9b2f3 76 |Feed Rate Mode | G93, **G94**|
Sergunb 0:9dcf85d9b2f3 77 |Units Mode | G20, **G21**|
Sergunb 0:9dcf85d9b2f3 78 |Cutter Radius Compensation | **G40** |
Sergunb 0:9dcf85d9b2f3 79 |Tool Length Offset |G43.1, **G49**|
Sergunb 0:9dcf85d9b2f3 80 |Program Mode | **M0**, M1, M2, M30|
Sergunb 0:9dcf85d9b2f3 81 |Spindle State |M3, M4, **M5**|
Sergunb 0:9dcf85d9b2f3 82 |Coolant State | M7, M8, **M9** |
Sergunb 0:9dcf85d9b2f3 83 |Override Control | _M56_ |
Sergunb 0:9dcf85d9b2f3 84
Sergunb 0:9dcf85d9b2f3 85 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.
Sergunb 0:9dcf85d9b2f3 86
Sergunb 0:9dcf85d9b2f3 87 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.
Sergunb 0:9dcf85d9b2f3 88
Sergunb 0:9dcf85d9b2f3 89 #### `$I` - View build info
Sergunb 0:9dcf85d9b2f3 90 This prints feedback to the user the Grbl version and source code build date. Optionally, `$I` can also store a short string to help identify which CNC machine you are communicating with, if you have more than machine using Grbl. To set this string, send Grbl `$I=xxx`, where `xxx` is your customization string that is less than 80 characters. The next time you query Grbl with a `$I` view build info, Grbl will print this string after the version and build date.
Sergunb 0:9dcf85d9b2f3 91
Sergunb 0:9dcf85d9b2f3 92 NOTE: Some OEMs may block access to over-writing the build info string so they can store product information and codes there.
Sergunb 0:9dcf85d9b2f3 93
Sergunb 0:9dcf85d9b2f3 94 #### $N - View startup blocks
Sergunb 0:9dcf85d9b2f3 95
Sergunb 0:9dcf85d9b2f3 96 `$Nx` are the startup blocks that Grbl runs every time you power on Grbl or reset Grbl. In other words, a startup block is a line of G-code that you can have Grbl auto-magically run to set your G-code modal defaults, or anything else you need Grbl to do everytime you start up your machine. Grbl can store two blocks of G-code as a system default.
Sergunb 0:9dcf85d9b2f3 97
Sergunb 0:9dcf85d9b2f3 98 So, when connected to Grbl, type `$N` and then enter. Grbl should respond with something short like:
Sergunb 0:9dcf85d9b2f3 99 ```
Sergunb 0:9dcf85d9b2f3 100 $N0=
Sergunb 0:9dcf85d9b2f3 101 $N1=
Sergunb 0:9dcf85d9b2f3 102 ok
Sergunb 0:9dcf85d9b2f3 103 ```
Sergunb 0:9dcf85d9b2f3 104 Not much to go on, but this just means that there is no G-code block stored in line `$N0` for Grbl to run upon startup. `$N1` is the next line to be run.
Sergunb 0:9dcf85d9b2f3 105
Sergunb 0:9dcf85d9b2f3 106 #### $Nx=line - Save startup block
Sergunb 0:9dcf85d9b2f3 107
Sergunb 0:9dcf85d9b2f3 108 **IMPORTANT: Be very careful when storing any motion (G0/1,G2/3,G28/30) commands in the startup blocks. These motion commands will run everytime you reset or power up Grbl, so if you have an emergency situation and have to e-stop and reset, a startup block move can and will likely make things worse quickly. Also, do not place any commands that save data to EEPROM, such as G10/G28.1/G30.1. This will cause Grbl to constantly re-write this data upon every startup and reset, which will eventually wear out your Arduino's EEPROM.**
Sergunb 0:9dcf85d9b2f3 109
Sergunb 0:9dcf85d9b2f3 110 **Typical usage for a startup block is simply to set your preferred modal states, such as G20 inches mode, always default to a different work coordinate system, or, to provide a way for a user to run some user-written unique feature that they need for their crazy project.**
Sergunb 0:9dcf85d9b2f3 111
Sergunb 0:9dcf85d9b2f3 112 To set a startup block, type `$N0=` followed by a valid G-code block and an enter. Grbl will run the block to check if it's valid and then reply with an `ok` or an `error:` to tell you if it's successful or something went wrong. If there is an error, Grbl will not save it.
Sergunb 0:9dcf85d9b2f3 113
Sergunb 0:9dcf85d9b2f3 114 For example, say that you want to use your first startup block `$N0` to set your G-code parser modes like G54 work coordinate, G20 inches mode, G17 XY-plane. You would type `$N0=G20 G54 G17` with an enter and you should see an `ok` response. You can then check if it got stored by typing `$N` and you should now see a response like `$N0=G20G54G17`.
Sergunb 0:9dcf85d9b2f3 115
Sergunb 0:9dcf85d9b2f3 116 Once you have a startup block stored in Grbl's EEPROM, everytime you startup or reset you will see your startup block printed back to you, starting with an open-chevron `>`, and a `:ok` response from Grbl to indicate if it ran okay. So for the previous example, you'll see:
Sergunb 0:9dcf85d9b2f3 117
Sergunb 0:9dcf85d9b2f3 118 ```
Sergunb 0:9dcf85d9b2f3 119 Grbl 1.1d ['$' for help]
Sergunb 0:9dcf85d9b2f3 120 >G20G54G17:ok
Sergunb 0:9dcf85d9b2f3 121
Sergunb 0:9dcf85d9b2f3 122 ```
Sergunb 0:9dcf85d9b2f3 123 If you have multiple G-code startup blocks, they will print back to you in order upon every startup. And if you'd like to clear one of the startup blocks, (e.g., block 0) type `$N0=` without anything following the equal sign.
Sergunb 0:9dcf85d9b2f3 124
Sergunb 0:9dcf85d9b2f3 125 NOTE: There are two variations on when startup blocks with run. First, it will not run if Grbl initializes up in an ALARM state or exits an ALARM state via an `$X` unlock for safety reasons. Always address and cancel the ALARM and then finish by a reset, where the startup blocks will run at initialization. Second, if you have homing enabled, the startup blocks will execute immediately after a successful homing cycle, not at startup.
Sergunb 0:9dcf85d9b2f3 126
Sergunb 0:9dcf85d9b2f3 127 #### `$C` - Check gcode mode
Sergunb 0:9dcf85d9b2f3 128 This toggles the Grbl's gcode parser to take all incoming blocks and process them completely, as it would in normal operation, but it does not move any of the axes, ignores dwells, and powers off the spindle and coolant. This is intended as a way to provide the user a way to check how their new G-code program fares with Grbl's parser and monitor for any errors (and checks for soft limit violations, if enabled).
Sergunb 0:9dcf85d9b2f3 129
Sergunb 0:9dcf85d9b2f3 130 When toggled off, Grbl will perform an automatic soft-reset (^X). This is for two purposes. It simplifies the code management a bit. But, it also prevents users from starting a job when their G-code modes are not what they think they are. A system reset always gives the user a fresh, consistent start.
Sergunb 0:9dcf85d9b2f3 131
Sergunb 0:9dcf85d9b2f3 132 #### `$X` - Kill alarm lock
Sergunb 0:9dcf85d9b2f3 133 Grbl's alarm mode is a state when something has gone critically wrong, such as a hard limit or an abort during a cycle, or if Grbl doesn't know its position. By default, if you have homing enabled and power-up the Arduino, Grbl enters the alarm state, because it does not know its position. The alarm mode will lock all G-code commands until the '$H' homing cycle has been performed. Or if a user needs to override the alarm lock to move their axes off their limit switches, for example, '$X' kill alarm lock will override the locks and allow G-code functions to work again.
Sergunb 0:9dcf85d9b2f3 134
Sergunb 0:9dcf85d9b2f3 135 But, tread carefully!! This should only be used in emergency situations. The position has likely been lost, and Grbl may not be where you think it is. So, it's advised to use G91 incremental mode to make short moves. Then, perform a homing cycle or reset immediately afterwards.
Sergunb 0:9dcf85d9b2f3 136
Sergunb 0:9dcf85d9b2f3 137 As noted earlier, startup lines do not execute after a `$X` command. Always reset when you have cleared the alarm and fixed the scenario that caused it. When Grbl resets to idle, the startup lines will then run as normal.
Sergunb 0:9dcf85d9b2f3 138
Sergunb 0:9dcf85d9b2f3 139 #### `$H` - Run homing cycle
Sergunb 0:9dcf85d9b2f3 140 This command is the only way to perform the homing cycle in Grbl. Some other motion controllers designate a special G-code command to run a homing cycle, but this is incorrect according to the G-code standards. Homing is a completely separate command handled by the controller.
Sergunb 0:9dcf85d9b2f3 141
Sergunb 0:9dcf85d9b2f3 142 TIP: After running a homing cycle, rather jogging manually all the time to a position in the middle of your workspace volume. You can set a G28 or G30 pre-defined position to be your post-homing position, closer to where you'll be machining. To set these, you'll first need to jog your machine to where you would want it to move to after homing. Type G28.1 (or G30.1) to have Grbl store that position. So then after '$H' homing, you could just enter 'G28' (or 'G30') and it'll move there auto-magically. In general, I would just move the XY axis to the center and leave the Z-axis up. This ensures that there isn't a chance the tool in the spindle will interfere and that it doesn't catch on anything.
Sergunb 0:9dcf85d9b2f3 143
Sergunb 0:9dcf85d9b2f3 144 #### `$Jx=line` - Run jogging motion
Sergunb 0:9dcf85d9b2f3 145
Sergunb 0:9dcf85d9b2f3 146 New to Grbl v1.1, this command will execute a special jogging motion. There are three main differences between a jogging motion and a motion commanded by a g-code line.
Sergunb 0:9dcf85d9b2f3 147
Sergunb 0:9dcf85d9b2f3 148 - Like normal g-code commands, several jog motions may be queued into the planner buffer, but the jogging can be easily canceled by a jog-cancel or feed-hold real-time command. Grbl will immediately hold the current jog and then automatically purge the buffers of any remaining commands.
Sergunb 0:9dcf85d9b2f3 149 - Jog commands are completely independent of the g-code parser state. It will not change any modes like `G91` incremental distance mode. So, you no longer have to make sure that you change it back to `G90` absolute distance mode afterwards. This helps reduce the chance of starting with the wrong g-code modes enabled.
Sergunb 0:9dcf85d9b2f3 150 - If soft-limits are enabled, any jog command that exceeds a soft-limit will simply return an error. It will not throw an alarm as it would with a normal g-code command. This allows for a much more enjoyable and fluid GUI or joystick interaction.
Sergunb 0:9dcf85d9b2f3 151
Sergunb 0:9dcf85d9b2f3 152 Executing a jog requires a specific command structure, as described below:
Sergunb 0:9dcf85d9b2f3 153
Sergunb 0:9dcf85d9b2f3 154 - The first three characters must be '$J=' to indicate the jog.
Sergunb 0:9dcf85d9b2f3 155 - The jog command follows immediate after the '=' and works like a normal G1 command.
Sergunb 0:9dcf85d9b2f3 156 - Feed rate is only interpreted in G94 units per minute. A prior G93 state is ignored during jog.
Sergunb 0:9dcf85d9b2f3 157 - Required words:
Sergunb 0:9dcf85d9b2f3 158 - XYZ: One or more axis words with target value.
Sergunb 0:9dcf85d9b2f3 159 - F - Feed rate value. NOTE: Each jog requires this value and is not treated as modal.
Sergunb 0:9dcf85d9b2f3 160 - Optional words: Jog executes based on current G20/G21 and G90/G91 g-code parser state. If one of the following optional words is passed, that state is overridden for one command only.
Sergunb 0:9dcf85d9b2f3 161 - G20 or G21 - Inch and millimeter mode
Sergunb 0:9dcf85d9b2f3 162 - G90 or G91 - Absolute and incremental distances
Sergunb 0:9dcf85d9b2f3 163 - G53 - Move in machine coordinates
Sergunb 0:9dcf85d9b2f3 164 - All other g-codes, m-codes, and value words are not accepted in the jog command.
Sergunb 0:9dcf85d9b2f3 165 - Spaces and comments are allowed in the command. These are removed by the pre-parser.
Sergunb 0:9dcf85d9b2f3 166
Sergunb 0:9dcf85d9b2f3 167 - Example: G21 and G90 are active modal states prior to jogging. These are sequential commands.
Sergunb 0:9dcf85d9b2f3 168 - `$J=X10.0 Y-1.5` will move to X=10.0mm and Y=-1.5mm in work coordinate frame (WPos).
Sergunb 0:9dcf85d9b2f3 169 - `$J=G91 G20 X0.5` will move +0.5 inches (12.7mm) to X=22.7mm (WPos). Note that G91 and G20 are only applied to this jog command.
Sergunb 0:9dcf85d9b2f3 170 - `$J=G53 Y5.0` will move the machine to Y=5.0mm in the machine coordinate frame (MPos). If the work coordinate offset for the y-axis is 2.0mm, then Y is 3.0mm in (WPos).
Sergunb 0:9dcf85d9b2f3 171
Sergunb 0:9dcf85d9b2f3 172 Jog commands behave almost identically to normal g-code streaming. Every jog command will
Sergunb 0:9dcf85d9b2f3 173 return an 'ok' when the jogging motion has been parsed and is setup for execution. If a
Sergunb 0:9dcf85d9b2f3 174 command is not valid or exceeds a soft-limit, Grbl will return an 'error:'. Multiple jogging commands may be queued in sequence.
Sergunb 0:9dcf85d9b2f3 175
Sergunb 0:9dcf85d9b2f3 176 NOTE: See additional jogging documentation for details on using this command to create a low-latency joystick or rotary dial interface.
Sergunb 0:9dcf85d9b2f3 177
Sergunb 0:9dcf85d9b2f3 178
Sergunb 0:9dcf85d9b2f3 179 #### `$RST=$`, `$RST=#`, and `$RST=*`- Restore Grbl settings and data to defaults
Sergunb 0:9dcf85d9b2f3 180 These commands are not listed in the main Grbl `$` help message, but are available to allow users to restore parts of or all of Grbl's EEPROM data. Note: Grbl will automatically reset after executing one of these commands to ensure the system is initialized correctly.
Sergunb 0:9dcf85d9b2f3 181
Sergunb 0:9dcf85d9b2f3 182 - `$RST=$` : Erases and restores the `$$` Grbl settings back to defaults, which is defined by the default settings file used when compiling Grbl. Often OEMs will build their Grbl firmwares with their machine-specific recommended settings. This provides users and OEMs a quick way to get back to square-one, if something went awry or if a user wants to start over.
Sergunb 0:9dcf85d9b2f3 183 - `$RST=#` : Erases and zeros all G54-G59 work coordinate offsets and G28/30 positions stored in EEPROM. These are generally the values seen in the `$#` parameters printout. This provides an easy way to clear these without having to do it manually for each set with a `G20 L2/20` or `G28.1/30.1` command.
Sergunb 0:9dcf85d9b2f3 184 - `$RST=*` : This clears and restores all of the EEPROM data used by Grbl. This includes `$$` settings, `$#` parameters, `$N` startup lines, and `$I` build info string. Note that this doesn't wipe the entire EEPROM, only the data areas Grbl uses. To do a complete wipe, please use the Arduino IDE's EEPROM clear example project.
Sergunb 0:9dcf85d9b2f3 185
Sergunb 0:9dcf85d9b2f3 186 NOTE: Some OEMs may restrict some or all of these commands to prevent certain data they use from being wiped.
Sergunb 0:9dcf85d9b2f3 187
Sergunb 0:9dcf85d9b2f3 188 #### `$SLP` - Enable Sleep Mode
Sergunb 0:9dcf85d9b2f3 189
Sergunb 0:9dcf85d9b2f3 190 This command will place Grbl into a de-powered sleep state, shutting down the spindle, coolant, and stepper enable pins and block any commands. It may only be exited by a soft-reset or power-cycle. Once re-initialized, Grbl will automatically enter an ALARM state, because it's not sure where it is due to the steppers being disabled.
Sergunb 0:9dcf85d9b2f3 191
Sergunb 0:9dcf85d9b2f3 192 This feature is useful if you need to automatically de-power everything at the end of a job by adding this command at the end of your g-code program, BUT, it is highly recommended that you add commands to first move your machine to a safe parking location prior to this sleep command. It also should be emphasized that you should have a reliable CNC machine that will disable everything when its supposed to, like your spindle. Grbl is not responsible for any damage it may cause. It's never a good idea to leave your machine unattended. So, use this command with the utmost caution!
Sergunb 0:9dcf85d9b2f3 193
Sergunb 0:9dcf85d9b2f3 194
Sergunb 0:9dcf85d9b2f3 195 ***
Sergunb 0:9dcf85d9b2f3 196
Sergunb 0:9dcf85d9b2f3 197 ## Grbl v1.1 Realtime commands
Sergunb 0:9dcf85d9b2f3 198
Sergunb 0:9dcf85d9b2f3 199 Realtime commands are single control characters that may be sent to Grbl to command and perform an action in real-time. This means that they can be sent at anytime, anywhere, and Grbl will immediately respond, regardless of what it is doing at the time. These commands include a reset, feed hold, resume, status report query, and overrides (in v1.1).
Sergunb 0:9dcf85d9b2f3 200
Sergunb 0:9dcf85d9b2f3 201 A realtime command:
Sergunb 0:9dcf85d9b2f3 202
Sergunb 0:9dcf85d9b2f3 203 - Will execute within tens of milliseconds.
Sergunb 0:9dcf85d9b2f3 204
Sergunb 0:9dcf85d9b2f3 205 - Is a single character that may be sent to Grbl at any time.
Sergunb 0:9dcf85d9b2f3 206
Sergunb 0:9dcf85d9b2f3 207 - Does not require a line feed or carriage return after them.
Sergunb 0:9dcf85d9b2f3 208
Sergunb 0:9dcf85d9b2f3 209 - Is not considered a part of the streaming protocol.
Sergunb 0:9dcf85d9b2f3 210
Sergunb 0:9dcf85d9b2f3 211 - Are intercepted when they are received and never placed in a buffer to be parsed by Grbl.
Sergunb 0:9dcf85d9b2f3 212
Sergunb 0:9dcf85d9b2f3 213 - Will ignore multiple commands until it has executed the first received command.
Sergunb 0:9dcf85d9b2f3 214
Sergunb 0:9dcf85d9b2f3 215 - May be tied to an input pin and may be operated with a button or switch.
Sergunb 0:9dcf85d9b2f3 216
Sergunb 0:9dcf85d9b2f3 217 - Actions depends on state or what Grbl is doing. It may not do anything.
Sergunb 0:9dcf85d9b2f3 218
Sergunb 0:9dcf85d9b2f3 219 - Descriptions explain how they work and what to expect.
Sergunb 0:9dcf85d9b2f3 220
Sergunb 0:9dcf85d9b2f3 221 #### ASCII Realtime Command Descriptions
Sergunb 0:9dcf85d9b2f3 222 Four realtime commands are type-able by users on a keyboard and shown in the `$` Grbl help message. These realtime command characters control some of Grbl's basic functions.
Sergunb 0:9dcf85d9b2f3 223
Sergunb 0:9dcf85d9b2f3 224 - `0x18` (ctrl-x) : Soft-Reset
Sergunb 0:9dcf85d9b2f3 225
Sergunb 0:9dcf85d9b2f3 226 - Immediately halts and safely resets Grbl without a power-cycle.
Sergunb 0:9dcf85d9b2f3 227 - Accepts and executes this command at any time.
Sergunb 0:9dcf85d9b2f3 228 - If reset while in motion, Grbl will throw an alarm to indicate position may be lost from the motion halt.
Sergunb 0:9dcf85d9b2f3 229 - If reset while in not motion, position is retained and re-homing is not required.
Sergunb 0:9dcf85d9b2f3 230 - An input pin is available to connect a button or switch.
Sergunb 0:9dcf85d9b2f3 231
Sergunb 0:9dcf85d9b2f3 232
Sergunb 0:9dcf85d9b2f3 233 - `?` : Status Report Query
Sergunb 0:9dcf85d9b2f3 234
Sergunb 0:9dcf85d9b2f3 235 - Immediately generates and sends back runtime data with a status report.
Sergunb 0:9dcf85d9b2f3 236 - Accepts and executes this command at any time, except during a homing cycle and when critical alarm (hard/soft limit error) is thrown.
Sergunb 0:9dcf85d9b2f3 237
Sergunb 0:9dcf85d9b2f3 238
Sergunb 0:9dcf85d9b2f3 239 - `~` : Cycle Start / Resume
Sergunb 0:9dcf85d9b2f3 240
Sergunb 0:9dcf85d9b2f3 241 - Resumes a feed hold, a safety door/parking state when the door is closed, and the M0 program pause states.
Sergunb 0:9dcf85d9b2f3 242 - Command is otherwise ignored.
Sergunb 0:9dcf85d9b2f3 243 - If the parking compile-time option is enabled and the safety door state is ready to resume, Grbl will re-enable the spindle and coolant, move back into position, and then resume.
Sergunb 0:9dcf85d9b2f3 244 - An input pin is available to connect a button or switch.
Sergunb 0:9dcf85d9b2f3 245
Sergunb 0:9dcf85d9b2f3 246
Sergunb 0:9dcf85d9b2f3 247 - `!` : Feed Hold
Sergunb 0:9dcf85d9b2f3 248
Sergunb 0:9dcf85d9b2f3 249 - Places Grbl into a suspend or HOLD state. If in motion, the machine will decelerate to a stop and then be suspended.
Sergunb 0:9dcf85d9b2f3 250 - Command executes when Grbl is in an IDLE, RUN, or JOG state. It is otherwise ignored.
Sergunb 0:9dcf85d9b2f3 251 - If jogging, a feed hold will cancel the jog motion and flush all remaining jog motions in the planner buffer. The state will return from JOG to IDLE or DOOR, if was detected as ajar during the active hold.
Sergunb 0:9dcf85d9b2f3 252 - By machine control definition, a feed hold does not disable the spindle or coolant. Only motion.
Sergunb 0:9dcf85d9b2f3 253 - An input pin is available to connect a button or switch.
Sergunb 0:9dcf85d9b2f3 254
Sergunb 0:9dcf85d9b2f3 255
Sergunb 0:9dcf85d9b2f3 256 #### Extended-ASCII Realtime Command Descriptions
Sergunb 0:9dcf85d9b2f3 257
Sergunb 0:9dcf85d9b2f3 258 Grbl v1.1 installed more than a dozen new realtime commands to control feed, rapid, and spindle overrides. To help prevent users from inadvertently altering overrides with a keystroke and allow for more commands later on, all of the new control characters have been moved to the extended ASCII character set. These are not easily type-able on a keyboard, but, depending on the OS, they may be entered using specific keystroke and code. GUI developers will need to be able to send extended ASCII characters, values `128 (0x80)` to `255 (0xFF)`, to Grbl to take advantage of these new features.
Sergunb 0:9dcf85d9b2f3 259
Sergunb 0:9dcf85d9b2f3 260 - `0x84` : Safety Door
Sergunb 0:9dcf85d9b2f3 261
Sergunb 0:9dcf85d9b2f3 262 - Although typically connected to an input pin to detect the opening of a safety door, this command allows a GUI to enact the safety door behavior with this command.
Sergunb 0:9dcf85d9b2f3 263 - Immediately suspends into a DOOR state and disables the spindle and coolant. If in motion, the machine will decelerate to a stop and then be suspended.
Sergunb 0:9dcf85d9b2f3 264 - If executed during homing, Grbl will instead halt motion and throw a homing alarm.
Sergunb 0:9dcf85d9b2f3 265 - If already in a suspend state or HOLD, the DOOR state supersedes it.
Sergunb 0:9dcf85d9b2f3 266 - If the parking compile-time option is enabled, Grbl will park the spindle to a specified location.
Sergunb 0:9dcf85d9b2f3 267 - Command executes when Grbl is in an IDLE, HOLD, RUN, HOMING, or JOG state. It is otherwise ignored.
Sergunb 0:9dcf85d9b2f3 268 - If jogging, a safety door will cancel the jog and all queued motions in the planner buffer. When the safety door is closed and resumed, Grbl will return to an IDLE state.
Sergunb 0:9dcf85d9b2f3 269 - An input pin is available to connect a button or switch, if enabled with a compile-time option.
Sergunb 0:9dcf85d9b2f3 270 - Some builds of Grbl v0.9 used the `@` character for this command, but it was undocumented. Moved to extended-ASCII to prevent accidental commanding.
Sergunb 0:9dcf85d9b2f3 271
Sergunb 0:9dcf85d9b2f3 272
Sergunb 0:9dcf85d9b2f3 273 - `0x85` : Jog Cancel
Sergunb 0:9dcf85d9b2f3 274
Sergunb 0:9dcf85d9b2f3 275 - Immediately cancels the current jog state by a feed hold and automatically flushing any remaining jog commands in the buffer.
Sergunb 0:9dcf85d9b2f3 276 - Command is ignored, if not in a JOG state or if jog cancel is already invoked and in-process.
Sergunb 0:9dcf85d9b2f3 277 - Grbl will return to the IDLE state or the DOOR state, if the safety door was detected as ajar during the cancel.
Sergunb 0:9dcf85d9b2f3 278
Sergunb 0:9dcf85d9b2f3 279
Sergunb 0:9dcf85d9b2f3 280 - Feed Overrides
Sergunb 0:9dcf85d9b2f3 281
Sergunb 0:9dcf85d9b2f3 282 - Immediately alters the feed override value. An active feed motion is altered within tens of milliseconds.
Sergunb 0:9dcf85d9b2f3 283 - Does not alter rapid rates, which include G0, G28, and G30, or jog motions.
Sergunb 0:9dcf85d9b2f3 284 - Feed override value can not be 10% or greater than 200%.
Sergunb 0:9dcf85d9b2f3 285 - If feed override value does not change, the command is ignored.
Sergunb 0:9dcf85d9b2f3 286 - Feed override range and increments may be changed in config.h.
Sergunb 0:9dcf85d9b2f3 287 - The commands are:
Sergunb 0:9dcf85d9b2f3 288 - `0x90` : Set 100% of programmed rate.
Sergunb 0:9dcf85d9b2f3 289 - `0x91` : Increase 10%
Sergunb 0:9dcf85d9b2f3 290 - `0x92` : Decrease 10%
Sergunb 0:9dcf85d9b2f3 291 - `0x93` : Increase 1%
Sergunb 0:9dcf85d9b2f3 292 - `0x94` : Decrease 1%
Sergunb 0:9dcf85d9b2f3 293
Sergunb 0:9dcf85d9b2f3 294
Sergunb 0:9dcf85d9b2f3 295 - Rapid Overrides
Sergunb 0:9dcf85d9b2f3 296
Sergunb 0:9dcf85d9b2f3 297 - Immediately alters the rapid override value. An active rapid motion is altered within tens of milliseconds.
Sergunb 0:9dcf85d9b2f3 298 - Only effects rapid motions, which include G0, G28, and G30.
Sergunb 0:9dcf85d9b2f3 299 - If rapid override value does not change, the command is ignored.
Sergunb 0:9dcf85d9b2f3 300 - Rapid override set values may be changed in config.h.
Sergunb 0:9dcf85d9b2f3 301 - The commands are:
Sergunb 0:9dcf85d9b2f3 302 - `0x95` : Set to 100% full rapid rate.
Sergunb 0:9dcf85d9b2f3 303 - `0x96` : Set to 50% of rapid rate.
Sergunb 0:9dcf85d9b2f3 304 - `0x97` : Set to 25% of rapid rate.
Sergunb 0:9dcf85d9b2f3 305
Sergunb 0:9dcf85d9b2f3 306
Sergunb 0:9dcf85d9b2f3 307 - Spindle Speed Overrides
Sergunb 0:9dcf85d9b2f3 308
Sergunb 0:9dcf85d9b2f3 309 - Immediately alters the spindle speed override value. An active spindle speed is altered within tens of milliseconds.
Sergunb 0:9dcf85d9b2f3 310 - Override values may be changed at any time, regardless of if the spindle is enabled or disabled.
Sergunb 0:9dcf85d9b2f3 311 - Spindle override value can not be 10% or greater than 200%
Sergunb 0:9dcf85d9b2f3 312 - If spindle override value does not change, the command is ignored.
Sergunb 0:9dcf85d9b2f3 313 - Spindle override range and increments may be altered in config.h.
Sergunb 0:9dcf85d9b2f3 314 - The commands are:
Sergunb 0:9dcf85d9b2f3 315 - `0x99` : Set 100% of programmed spindle speed
Sergunb 0:9dcf85d9b2f3 316 - `0x9A` : Increase 10%
Sergunb 0:9dcf85d9b2f3 317 - `0x9B` : Decrease 10%
Sergunb 0:9dcf85d9b2f3 318 - `0x9C` : Increase 1%
Sergunb 0:9dcf85d9b2f3 319 - `0x9D` : Decrease 1%
Sergunb 0:9dcf85d9b2f3 320
Sergunb 0:9dcf85d9b2f3 321
Sergunb 0:9dcf85d9b2f3 322 - `0x9E` : Toggle Spindle Stop
Sergunb 0:9dcf85d9b2f3 323
Sergunb 0:9dcf85d9b2f3 324 - Toggles spindle enable or disable state immediately, but only while in the HOLD state.
Sergunb 0:9dcf85d9b2f3 325 - The command is otherwise ignored, especially while in motion. This prevents accidental disabling during a job that can either destroy the part/machine or cause personal injury. Industrial machines handle the spindle stop override similarly.
Sergunb 0:9dcf85d9b2f3 326 - When motion restarts via cycle start, the last spindle state will be restored and wait 4.0 seconds (configurable) before resuming the tool path. This ensures the user doesn't forget to turn it back on.
Sergunb 0:9dcf85d9b2f3 327 - While disabled, spindle speed override values may still be altered and will be in effect once the spindle is re-enabled.
Sergunb 0:9dcf85d9b2f3 328 - If a safety door is opened, the DOOR state will supersede the spindle stop override, where it will manage the spindle re-energizing itself upon closing the door and resuming. The prior spindle stop override state is cleared and reset.
Sergunb 0:9dcf85d9b2f3 329
Sergunb 0:9dcf85d9b2f3 330
Sergunb 0:9dcf85d9b2f3 331 - `0xA0` : Toggle Flood Coolant
Sergunb 0:9dcf85d9b2f3 332
Sergunb 0:9dcf85d9b2f3 333 - Toggles flood coolant state and output pin until the next toggle or g-code command alters it.
Sergunb 0:9dcf85d9b2f3 334 - May be commanded at any time while in IDLE, RUN, or HOLD states. It is otherwise ignored.
Sergunb 0:9dcf85d9b2f3 335 - This override directly changes the coolant modal state in the g-code parser. Grbl will continue to operate normally like it received and executed an `M8` or `M9` g-code command.
Sergunb 0:9dcf85d9b2f3 336 - When `$G` g-code parser state is queried, the toggle override change will be reflected by an `M8` enabled or disabled with an `M9` or not appearing when `M7` is present.
Sergunb 0:9dcf85d9b2f3 337
Sergunb 0:9dcf85d9b2f3 338
Sergunb 0:9dcf85d9b2f3 339 - `0xA1` : Toggle Mist Coolant
Sergunb 0:9dcf85d9b2f3 340
Sergunb 0:9dcf85d9b2f3 341 - Enabled by `ENABLE_M7` compile-time option. Default is disabled.
Sergunb 0:9dcf85d9b2f3 342 - Toggles mist coolant state and output pin until the next toggle or g-code command alters it.
Sergunb 0:9dcf85d9b2f3 343 - May be commanded at any time while in IDLE, RUN, or HOLD states. It is otherwise ignored.
Sergunb 0:9dcf85d9b2f3 344 - This override directly changes the coolant modal state in the g-code parser. Grbl will continue to operate normally like it received and executed an `M7` or `M9` g-code command.
Sergunb 0:9dcf85d9b2f3 345 - When `$G` g-code parser state is queried, the toggle override change will be reflected by an `M7` enabled or disabled with an `M9` or not appearing when `M8` is present.