Arduino

Card System Raspberry

PC System Linux
PC System WIN

Least Expensive  Arduino
Least Bulky is Raspberry overall.
Most Flexible is Computer

Work Flow: Sketchup > SketchUcam Plugin  or  MakerCam-online  > Universal G-code Uploader > Arduino
Work Flow: Sketchup > Camplugin or  MakerCam-online  > Ethernet > Raspberry PI > Universal G-code Uploader > Arduino
Alternative to Universal G-Code  GRBL Controller

Sketchup with SVG plugin for Maker Cam
Maker Cam







Arduino
or
Card System


Link
Link Tutorial   Link
Universal G-code Sender


Library
Cameras
Arduino
(No Parallel Cord)
Raspberry
Card System
Computer
Arduino Nano
$10 + $6 for the terminal board.
Cheap controllers are $12
~~$64

$25 + Arduino = $19.95 + $4 for power supply.  ~$50-
Arduino  IDE on Mac


Add GRBL library

Universal GCode Sender
Video  Touch Plate
Access software Arduino OSX Video
Software Link
Flash GRBL
Grbl Code
Hex Uploader

Hook Up Video


Case for Arduino Plus Shield
See Below



$32.50 / $43.95 + $35 for PI
~$70
HDMI Touch Screen?

Remote Potentiometer for power control.


MCP4151

PCSENSOR Controller


Universal G-code sender PI


Real VNC





$130-$220 Smoothie $170 Work Flow Linux
Board with memory for CNC is best.
Sketchup w/ SketuUCamplugin  >     Universal G-Code Uploader > control board or arduino
Work Flow Win

Sketchup w/ SketuUCamplugin  >     Universal G-Code Uploader > control board or arduino

Sketchup

Linux CNC needs parallel port. May be able to use Dell Computer.  from ~$70

LinuxCNC  EMC2

LinuxCNC(EMC2
Can be addressed via terminal or scripts.
Moving head Video?



 Interfaces as low as $15 try with moving head?
Getr one with memory so it can run repeats ~c $70
USB interface board $89 via Mach 3
PCI cord to Controller
Computer With LinuxCNC   Interface Card or Box $300 for controller x~$400 with card

https://buildyourcnc.com/Item/electronicsAndMotors-electronic-component-breakout-Mach3-USB-Board


Entry Level without memory?


Power Supply for Machine Stepper Motors  12-36 volts if using onboard drivers.
9 volts for Arduino
20 to 50vdc for Drivers

Thoughts:


Ideas: Use USB keystroke emulator for Stops or contactor and relays.
Cable for external drivers





Work Flows

Sketchup SketuUCamplugin Universal G-Code Uploader
Meshcam $250
Sketchup MakerCam G-Code Uploader

Makercam is online. Can do drilling.

STL Files into Meshcam

Machines
OX
Open Builds  Parts Store

Computers
Needs Adapter to USB. 
Use Parallel and Dell




Raspberry
External Driver Conversion $5

Link$43.98
Lesser priced $32.50

https://www.ebay.com/itm/Raspberry-Pi-CNC-Hat-V2-60-GRBL-v1-1-Compatible-Extra-Options-/272596155477

Linux

Win

OSX
Adapters to Parallel = Latency issues?
Use Sketchup Fix to Dropbox to Linux Machine With Parallel Card



Parallel Interfaces  
$19.95

Arduino Nano $8


Video Arduino can power drivers directly.




Arduino as interface  protoneer

Controlers
Using Uploader at this link/
https://blog.protoneer.co.nz/quick-grbl-setup-guide-for-windows-arduino-g-code-interpreter/



$20.00





Without Parallel Use Arduino


Connect to External Drivers



The breakout pins next to the X axis stepper and below the reset button is where the connection is made.

The pin-out is as follow:

Enable : Ground
X Step : X Direction
Y Step : Y Direction
Z Step : Z Direction

External drivers need only 4 signal pins to work. The pins are Ground , Enable , Step , Direction.

Take care to make sure the external drivers run on 5V logic voltage like the Arduino that is running GRBL.


Power Supply 0-48v adjustable.
Video
Variable Resistor Programable
https://www.arduino.cc/en/Tutorial/DigitalPotentiometer


Use DM542T  $34.00

http://amzn.to/2HLA6KC


$33.95


$19 for one below.


$13.00



alternative http://amzn.to/2G6wiXf

http://openbuildspartstore.com/dq542ma-stepper-motor-driver/

Phase in stepper motors refers to additional poles not supplied phases.



Controller Card Version
Tiny

Link

The software stack used at Spark is:





GRBL Arduino
Try this first! Paul Kaplan from Inventables made this process much easier than before with a simple GUI app called HexUploader. Let us know how it works!

Last updated: 2012-02-12 by gregrebholz. (Tested on OS X 10.7, 10.6, and 10.4 and the Arduino Uno and IDE v1.0/r22; and OS X 10.6 and the Arduino Duemilanove and IDE v1.0)

As with compiling grbl, the tools for flashing grbl to an Arduino are included in the Arduino IDE software. All you need to do is directly access them through the Terminal.app. The following instructions have been tested and work for the Arduino Uno. For others, your mileage may vary.

For most people, the path to the Arduino compiler tools will be: /Applications/Arduino.app/Contents/Resources/Java/hardware/tools/avr (Note the absence of /bin from the compiling grbl page.) Depending on where you place the Arduino IDE, the /Applications/Arduino.app path may be different. So, lets call your compiler tools path $AVRPATH to help shorten the following commands.

Next you will need to find the device path to your Arduino. First, connect your Arduino to a Mac USB port. To find the device path, from a Terminal.app window, type: /dev/tty.usb and hit Tab once or twice. This will either give you one device path, which is your Arduino, or multiple paths, if you have more than one usbmodem type device connected to your computer. If you have multiple, simply unplug your Arduino, repeat the process, and eliminate the remaining devices that are still listed. Your Arduino device path should be something like this: /dev/tty.usbmodem1811 and lets call this $DEVPATH.

To Flash Grbl: Using the Terminal.app, first make sure you're in the same directory as the grbl.hex file you want to flash to the Arduino, which we'll call $GRBLHEX. Then, type the following commands to flash.

For Release 0023 and prior on the Uno: $AVRPATH/bin/avrdude -C$AVRPATH/etc/avrdude.conf -pm328p -cstk500v1 -P$DEVPATH -D -Uflash:w:$GRBLHEX

For Release 0023 and prior on the Duemilanove: $AVRPATH/bin/avrdude -C$AVRPATH/etc/avrdude.conf -pm328p -cstk500v1 -P$DEVPATH -b57600 -D -Uflash:w:$GRBLHEX

For v1.0 on the Uno: $AVRPATH/bin/avrdude -C$AVRPATH/etc/avrdude.conf -pm328p -carduino -P$DEVPATH -D -Uflash:w:$GRBLHEX

For v1.0 on the Duemilanove: $AVRPATH/bin/avrdude -C$AVRPATH/etc/avrdude.conf -pm328p -carduino -P$DEVPATH -b57600 -D -Uflash:w:$GRBLHEX

Note the only change between the two versions is the -c flag from the stk500v1 programmer to the arduino programmer. This programmer flag was updated in the v1.0 IDE. If all goes according to plan, you should see three sequential progress bars of reading, writing, and verifying and you're good to go!


Link

List of Supported G-Codes in Grbl v1.1:
  - Non-Modal Commands: G4, G10L2, G10L20, G28, G30, G28.1, G30.1, G53, G92, G92.1
  - Motion Modes: G0, G1, G2, G3, G38.2, G38.3, G38.4, G38.5, G80
  - Feed Rate Modes: G93, G94
  - Unit Modes: G20, G21
  - Distance Modes: G90, G91
  - Arc IJK Distance Modes: G91.1
  - Plane Select Modes: G17, G18, G19
  - Tool Length Offset Modes: G43.1, G49
  - Cutter Compensation Modes: G40
  - Coordinate System Modes: G54, G55, G56, G57, G58, G59
  - Control Modes: G61
  - Program Flow: M0, M1, M2, M30*
  - Coolant Control: M7*, M8, M9
  - Spindle Control: M3, M4, M5
  - Valid Non-Command Words: F, I, J, K, L, N, P, R, S, T, X, Y, Z

Gcode

Code

Description Milling
( M )
Turning
( T )
Corollary info
G00 Rapid positioning M T On 2- or 3-axis moves, G00 (unlike G01) traditionally does not necessarily move in a single straight line between start point and end point. It moves each axis at its max speed until its vector quantity is achieved. Shorter vector usually finishes first (given similar axis speeds). This matters because it may yield a dog-leg or hockey-stick motion, which the programmer needs to consider, depending on what obstacles are nearby, to avoid a crash. Some machines offer interpolated rapids as a feature for ease of programming (safe to assume a straight line).
G01 Linear interpolation M T The most common workhorse code for feeding during a cut. The program specs the start and end points, and the control automatically calculates (interpolates) the intermediate points to pass through that yield a straight line (hence "linear"). The control then calculates the angular velocities at which to turn the axis leadscrews via their servomotors or stepper motors. The computer performs thousands of calculations per second, and the motors react quickly to each input. Thus the actual toolpath of the machining takes place with the given feedrate on a path that is accurately linear to within very small limits.
G02 Circular interpolation, clockwise M T Very similar in concept to G01. Again, the control interpolates intermediate points and commands the servo- or stepper motors to rotate the amount needed for the leadscrew to translate the motion to the correct tool tip positioning. This process repeated thousands of times per minute generates the desired toolpath. In the case of G02, the interpolation generates a circle rather than a line. As with G01, the actual toolpath of the machining takes place with the given feedrate on a path that accurately matches the ideal (in G02's case, a circle) to within very small limits. In fact, the interpolation is so precise (when all conditions are correct) that milling an interpolated circle can obviate operations such as drilling, and often even fine boring. Addresses for radius or arc center: G02 and G03 take either an R address (for the radius desired on the part) or IJK addresses (for the component vectors that define the vector from the arc start point to the arc center point). Cutter comp: On most controls you cannot start G41 or G42 in G02 or G03 modes. You must already have compensated in an earlier G01 block. Often, a short linear lead-in movement is programmed, merely to allow cutter compensation before the main action, the circle-cutting, begins. Full circles: When the arc start point and the arc end point are identical, the tool cuts a 360° arc (a full circle). (Some older controls do not support this because arcs cannot cross between quadrants of the cartesian system. Instead, they require four quarter-circle arcs programmed back-to-back.)
G03 Circular interpolation, counterclockwise M T Same corollary info as for G02.
G04 Dwell M T Takes an address for dwell period (may be X, U, or P). The dwell period is specified by a control parameter, typically set to milliseconds. Some machines can accept either X1.0 (s) or P1000 (ms), which are equivalent. Choosing dwell duration: Often the dwell needs only to last one or two full spindle rotations. This is typically much less than one second. Be aware when choosing a duration value that a long dwell is a waste of cycle time. In some situations it won't matter, but for high-volume repetitive production (over thousands of cycles), it is worth calculating that perhaps you only need 100 ms, and you can call it 200 to be safe, but 1000 is just a waste (too long).
G05 P10000 High-precision contour control (HPCC) M   Uses a deep look-ahead buffer and simulation processing to provide better axis movement acceleration and deceleration during contour milling
G05.1 Q1. AI Advanced Preview Control M   Uses a deep look-ahead buffer and simulation processing to provide better axis movement acceleration and deceleration during contour milling
G06.1 Non-uniform rational B-spline (NURBS) Machining M   Activates Non-Uniform Rational B Spline for complex curve and waveform machining (this code is confirmed in Mazatrol 640M ISO Programming)
G07 Imaginary axis designation M    
G09 Exact stop check, non-modal M T The modal version is G61.
G10 Programmable data input M T Modifies the value of work coordinate and tool offsets[8][7]
G11 Data write cancel M T  
G17 XY plane selection M    
G18 ZX plane selection M T
G19 YZ plane selection M    
G20 Programming in inches M T Somewhat uncommon except in USA and (to lesser extent) Canada and UK. However, in the global marketplace, competence with both G20 and G21 always stands some chance of being necessary at any time. The usual minimum increment in G20 is one ten-thousandth of an inch (0.0001"), which is a larger distance than the usual minimum increment in G21 (one thousandth of a millimeter, .001 mm, that is, one micrometre). This physical difference sometimes favors G21 programming.
G21 Programming in millimeters (mm) M T Prevalent worldwide. However, in the global marketplace, competence with both G20 and G21 always stands some chance of being necessary at any time.
G28 Return to home position (machine zero, aka machine reference point) M T Takes X Y Z addresses which define the intermediate point that the tool tip will pass through on its way home to machine zero. They are in terms of part zero (aka program zero), NOT machine zero.
G30 Return to secondary home position (machine zero, aka machine reference point) M T Takes a P address specifying which machine zero point to use if the machine has several secondary points (P1 to P4). Takes X Y Z addresses that define the intermediate point that the tool tip passes through on its way home to machine zero. These are expressed in terms of part zero (aka program zero), NOT machine zero.
G31 Feed until skip function M    Used for probes and tool length measurement systems.
G32 Single-point threading, longhand style (if not using a cycle, e.g., G76)   T Similar to G01 linear interpolation, except with automatic spindle synchronization for single-point threading.
G33 Constant-pitch threading M    
G33 Single-point threading, longhand style (if not using a cycle, e.g., G76)   T Some lathe controls assign this mode to G33 rather than G32.
G34 Variable-pitch threading M    
G40 Tool radius compensation off M T Turn off cutter radius compensation (CRC). Cancels G41 or G42.
G41 Tool radius compensation left M T Turn on cutter radius compensation (CRC), left, for climb milling.
Milling: Given righthand-helix cutter and M03 spindle direction, G41 corresponds to climb milling (down milling). Takes an address (D or H) that calls an offset register value for radius.
Turning: Often needs no D or H address on lathes, because whatever tool is active automatically calls its geometry offsets with it. (Each turret station is bound to its geometry offset register.)

G41 and G42 for milling has been partially automated and obviated (although not completely) since CAM programming has become more common. CAM systems let the user program as if using a zero-diameter cutter. The fundamental concept of cutter radius compensation is still in play (i.e., that the surface produced will be distance R away from the cutter center), but the programming mindset is different. The human does not choreograph the toolpath with conscious, painstaking attention to G41, G42, and G40, because the CAM software takes care of that. The software has various CRC mode selections, such as computer, control, wear, reverse wear, off, some of which do not use G41/G42 at all (good for roughing, or wide finish tolerances), and others that use it so that the wear offset can still be tweaked at the machine (better for tight finish tolerances).

G42 Tool radius compensation right M T Turn on cutter radius compensation (CRC), right, for conventional milling. Similar corollary info as for G41. Given righthand-helix cutter and M03 spindle direction, G42 corresponds to conventional milling (up milling).
G43 Tool height offset compensation negative M   Takes an address, usually H, to call the tool length offset register value. The value is negative because it will be added to the gauge line position. G43 is the commonly used version (vs G44).
G44 Tool height offset compensation positive M   Takes an address, usually H, to call the tool length offset register value. The value is positive because it will be subtracted from the gauge line position. G44 is the seldom-used version (vs G43).
G45 Axis offset single increase M    
G46 Axis offset single decrease M    
G47 Axis offset double increase M    
G48 Axis offset double decrease M    
G49 Tool length offset compensation cancel M   Cancels G43 or G44.
G50 Define the maximum spindle speed   T Takes an S address integer, which is interpreted as rpm. Without this feature, G96 mode (CSS) would rev the spindle to "wide open throttle" when closely approaching the axis of rotation.
G50 Scaling function cancel M    
G50 Position register (programming of vector from part zero to tool tip)   T Position register is one of the original methods to relate the part (program) coordinate system to the tool position, which indirectly relates it to the machine coordinate system, the only position the control really "knows". Not commonly programmed anymore because G54 to G59 (WCSs) are a better, newer method. Called via G50 for turning, G92 for milling. Those G addresses also have alternate meanings (which see). Position register can still be useful for datum shift programming. The "manual absolute" switch, which has very few useful applications in WCS contexts, was more useful in position register contexts, because it allowed the operator to move the tool to a certain distance from the part (for example, by touching off a 2.0000" gage) and then declare to the control what the distance-to-go shall be (2.0000).
G52 Local coordinate system (LCS) M   Temporarily shifts program zero to a new location. It is simply "an offset from an offset", that is, an additional offset added onto the WCS offset. This simplifies programming in some cases. The typical example is moving from part to part in a multipart setup. With G54 active, G52 X140.0 Y170.0 shifts program zero 140 mm over in X and 170 mm over in Y. When the part "over there" is done, G52 X0 Y0 returns program zero to normal G54 (by reducing G52 offset to nothing). The same result can also be achieved (1) using multiple WCS origins, G54/G55/G56/G57/G58/G59; (2) on newer controls, G54.1 P1/P2/P3/etc. (all the way up to P48); or (3) using G10 for programmable data input, in which the program can write new offset values to the offset registers.[7] The method to use depends on shop-specific application.
G53 Machine coordinate system M T Takes absolute coordinates (X,Y,Z,A,B,C) with reference to machine zero rather than program zero. Can be helpful for tool changes. Nonmodal and absolute only. Subsequent blocks are interpreted as "back to G54" even if it is not explicitly programmed.
G54 to G59 Work coordinate systems (WCSs) M T Have largely replaced position register (G50 and G92). Each tuple of axis offsets relates program zero directly to machine zero. Standard is 6 tuples (G54 to G59), with optional extensibility to 48 more via G54.1 P1 to P48.
G54.1 P1 to P48 Extended work coordinate systems M T Up to 48 more WCSs besides the 6 provided as standard by G54 to G59. Note floating-point extension of G-code data type (formerly all integers). Other examples have also evolved (e.g., G84.2). Modern controls have the hardware to handle it.
G61 Exact stop check, modal M T Can be canceled with G64. The non-modal version is G09.
G62 Automatic corner override M T  
G64 Default cutting mode (cancel exact stop check mode) M T Cancels G61.
G68 Rotate coordinate system M   Rotates coordinate system in the current plane given with G17, G18, or G19. Center of rotation is given with two parameters, which vary with each vendor's implementation. Rotate with angle given with argument R. This can be used, for instance, to align the coordinate system with a misaligned part. It can also be used to repeat movement sequences around a center. Not all vendors support coordinate system rotation.
G69 Turn off coordinate system rotation M   Cancels G68.
G70 Fixed cycle, multiple repetitive cycle, for finishing (including contours)   T  
G71 Fixed cycle, multiple repetitive cycle, for roughing (Z-axis emphasis)   T  
G72 Fixed cycle, multiple repetitive cycle, for roughing (X-axis emphasis)   T  
G73 Fixed cycle, multiple repetitive cycle, for roughing, with pattern repetition   T  
G73 Peck drilling cycle for milling – high-speed (NO full retraction from pecks) M   Retracts only as far as a clearance increment (system parameter). For when chipbreaking is the main concern, but chip clogging of flutes is not. Compare G83.
G74 Peck drilling cycle for turning   T  
G74 Tapping cycle for milling, lefthand thread, M04 spindle direction M   See notes at G84.
G75 Peck grooving cycle for turning   T  
G76 Fine boring cycle for milling M   Includes OSS and shift (oriented spindle stop and shift tool off centerline for retraction)
G76 Threading cycle for turning, multiple repetitive cycle   T  
G80 Cancel canned cycle M T Milling: Cancels all cycles such as G73, G81, G83, etc. Z-axis returns either to Z-initial level or R level, as programmed (G98 or G99, respectively).
Turning: Usually not needed on lathes, because a new group-1 G address (G00 to G03) cancels whatever cycle was active.
G81 Simple drilling cycle M   No dwell built in
G82 Drilling cycle with dwell M   Dwells at hole bottom (Z-depth) for the number of milliseconds specified by the P address. Good for when hole bottom finish matters. Good for spot drilling because the divot is certain to clean up evenly. Consider the "choosing dwell duration" note at G04.
G83 Peck drilling cycle (full retraction from pecks) M   Returns to R-level after each peck. Good for clearing flutes of chips. Compare G73.
G84 Tapping cycle, righthand thread, M03 spindle direction M   G74 and G84 are the righthand and lefthand "pair" for old-school tapping with a non-rigid toolholder ("tapping head" style). Compare the rigid tapping "pair", G84.2 and G84.3.
G84.2 Tapping cycle, righthand thread, M03 spindle direction, rigid toolholder M   See notes at G84. Rigid tapping synchronizes speed and feed according to the desired thread helix. That is, it synchronizes degrees of spindle rotation with microns of axial travel. Therefore, it can use a rigid toolholder to hold the tap. This feature is not available on old machines or newer low-end machines, which must use "tapping head" motion (G74/G84).
G84.3 Tapping cycle, lefthand thread, M04 spindle direction, rigid toolholder M   See notes at G84 and G84.2.
G85 boring cycle, feed in/feed out M  
  • Good cycle for a reamer.
  • In some cases good for single-point boring tool, although in other cases the lack of depth of cut on the way back out is bad for surface finish, in which case, G76 (OSS/shift) can be used instead.
  • If need dwell at hole bottom, see G89.
G86 boring cycle, feed in/spindle stop/rapid out M   Boring tool leaves a slight score mark on the way back out. Appropriate cycle for some applications; for others, G76 (OSS/shift) can be used instead.
G87 boring cycle, backboring M   For backboring. Returns to initial level only (G98); this cycle cannot use G99 because its R level is on the far side of the part, away from the spindle headstock.
G88 boring cycle, feed in/spindle stop/manual operation M    
G89 boring cycle, feed in/dwell/feed out M   G89 is like G85 but with dwell added at bottom of hole.
G90 Absolute programming M T (B) Positioning defined with reference to part zero.
Milling: Always as above.
Turning: Sometimes as above (Fanuc group type B and similarly designed), but on most lathes (Fanuc group type A and similarly designed), G90/G91 are not used for absolute/incremental modes. Instead, U and W are the incremental addresses and X and Z are the absolute addresses. On these lathes, G90 is instead a fixed cycle address for roughing.
G90 Fixed cycle, simple cycle, for roughing (Z-axis emphasis)   T (A) When not serving for absolute programming (above)
G91 Incremental programming M T (B) Positioning defined with reference to previous position.
Milling: Always as above.
Turning: Sometimes as above (Fanuc group type B and similarly designed), but on most lathes (Fanuc group type A and similarly designed), G90/G91 are not used for absolute/incremental modes. Instead, U and W are the incremental addresses and X and Z are the absolute addresses. On these lathes, G90 is a fixed cycle address for roughing.
G92 Position register (programming of vector from part zero to tool tip) M T (B) Same corollary info as at G50 position register.
Milling: Always as above.
Turning: Sometimes as above (Fanuc group type B and similarly designed), but on most lathes (Fanuc group type A and similarly designed), position register is G50.
G92 Threading cycle, simple cycle   T (A)  
G94 Feedrate per minute M T (B) On group type A lathes, feedrate per minute is G98.
G94 Fixed cycle, simple cycle, for roughing (X-axis emphasis)   T (A) When not serving for feedrate per minute (above)
G95 Feedrate per revolution M T (B) On group type A lathes, feedrate per revolution is G99.
G96 Constant surface speed (CSS)   T Varies spindle speed automatically to achieve a constant surface speed. See speeds and feeds. Takes an S address integer, which is interpreted as sfm in G20 mode or as m/min in G21 mode.
G97 Constant spindle speed M T Takes an S address integer, which is interpreted as rev/min (rpm). The default speed mode per system parameter if no mode is programmed.
G98 Return to initial Z level in canned cycle M    
G98 Feedrate per minute (group type A)   T (A) Feedrate per minute is G94 on group type B.
G99 Return to R level in canned cycle M    
G99 Feedrate per revolution (group type A)   T (A) Feedrate per revolution is G95 on group type B.
G100 Tool length measurement M    

List of M-codes commonly found on FANUC and similarly designed controls for milling and turning

Sources: Smid 2008;[4] Smid 2010;[5] Green et al. 1996.[6]

Some older controls require M codes to be in separate blocks (that is, not on the same line).

Code   Description Milling
( M )
Turning
( T )
Corollary info
M00 Compulsory stop M T Non-optional—machine always stops on reaching M00 in the program execution.
M01 Optional stop M T Machine only stops at M01 if operator pushes the optional stop button.
M02 End of program M T Program ends; execution may or may not return to program top (depending on the control); may or may not reset register values. M02 was the original program-end code, now considered obsolete, but still supported for backward compatibility.[9] Many modern controls treat M02 as equivalent to M30.[9] See M30 for additional discussion of control status upon executing M02 or M30.
M03 Spindle on (clockwise rotation) M T The speed of the spindle is determined by the address S, in either revolutions per minute (G97 mode; default) or surface feet per minute or [surface] meters per minute (G96 mode [CSS] under either G20 or G21). The right-hand rule can be used to determine which direction is clockwise and which direction is counter-clockwise.

Right-hand-helix screws moving in the tightening direction (and right-hand-helix flutes spinning in the cutting direction) are defined as moving in the M03 direction, and are labeled "clockwise" by convention. The M03 direction is always M03 regardless of local vantage point and local CW/CCW distinction.

M04 Spindle on (counterclockwise rotation) M T See comment above at M03.
M05 Spindle stop M T  
M06 Automatic tool change (ATC) M T (some-times) Many lathes do not use M06 because the T address itself indexes the turret.
Programming on any particular machine tool requires knowing which method that machine uses. To understand how the T address works and how it interacts (or not) with M06, one must study the various methods, such as lathe turret programming, ATC fixed tool selection, ATC random memory tool selection, the concept of "next tool waiting", and empty tools.[4]
M07 Coolant on (mist) M T  
M08 Coolant on (flood) M T  
M09 Coolant off M T  
M10 Pallet clamp on M   For machining centers with pallet changers
M11 Pallet clamp off M   For machining centers with pallet changers
M13 Spindle on (clockwise rotation) and coolant on (flood) M   This one M-code does the work of both M03 and M08. It is not unusual for specific machine models to have such combined commands, which make for shorter, more quickly written programs.
M19 Spindle orientation M T Spindle orientation is more often called within cycles (automatically) or during setup (manually), but it is also available under program control via M19. The abbreviation OSS (oriented spindle stop) may be seen in reference to an oriented stop within cycles.

The relevance of spindle orientation has increased as technology has advanced. Although 4- and 5-axis contour milling and CNC single-pointing have depended on spindle position encoders for decades, before the advent of widespread live tooling and mill-turn/turn-mill systems, it was not as often relevant in "regular" (non-"special") machining for the operator (as opposed to the machine) to know the angular orientation of a spindle as it is today, except in certain contexts (such as tool change, or G76 fine boring cycles with choreographed tool retraction). Most milling of features indexed around a turned workpiece was accomplished with separate operations on indexing head setups; in a sense, indexing heads were originally invented as separate pieces of equipment, to be used in separate operations, which could provide precise spindle orientation in a world where it otherwise mostly didn't exist (and didn't need to). But as CAD/CAM and multiaxis CNC machining with multiple rotary-cutter axes becomes the norm, even for "regular" (non-"special") applications, machinists now frequently care about stepping just about any spindle through its 360° with precision.

M21 Mirror, X-axis M    
M21 Tailstock forward   T  
M22 Mirror, Y-axis M    
M22 Tailstock backward   T  
M23 Mirror OFF M    
M23 Thread gradual pullout ON   T  
M24 Thread gradual pullout OFF   T  
M30 End of program, with return to program top M T Today, M30 is considered the standard program-end code, and returns execution to the top of the program. Most controls also still support the original program-end code, M02, usually by treating it as equivalent to M30. Additional info: Compare M02 with M30. First, M02 was created, in the days when the punched tape was expected to be short enough to splice into a continuous loop (which is why on old controls, M02 triggered no tape rewinding).[9] The other program-end code, M30, was added later to accommodate longer punched tapes, which were wound on a reel and thus needed rewinding before another cycle could start.[9] On many newer controls, there is no longer a difference in how the codes are executed—both act like M30.
M41 Gear select – gear 1   T  
M42 Gear select – gear 2   T  
M43 Gear select – gear 3   T  
M44 Gear select – gear 4   T  
M48 Feedrate override allowed M T  
M49 Feedrate override NOT allowed M T Prevent MFO. This rule is also usually called (automatically) within tapping cycles or single-point threading cycles, where feed is precisely correlated to speed. Same with spindle speed override (SSO) and feed hold button. Some controls are capable of providing SSO and MFO during threading.
M52 Unload Last tool from spindle M T Also empty spindle.
M60 Automatic pallet change (APC) M   For machining centers with pallet changers
M98 Subprogram call M T Takes an address P to specify which subprogram to call, for example, "M98 P8979" calls subprogram O8979.
M99 Subprogram end M T Usually placed at end of subprogram, where it returns execution control to the main program. The default is that control returns to the block following the M98 call in the main program. Return to a different block number can be specified by a P address. M99 can also be used in main program with block skip for endless loop of main program on bar work on lathes (until operator toggles block skip).