So technically the answer is yes but with caveats, the examples given above are for a wee little CNC / Laser engraver, almost every successful RPI based solution involves using a separate GRBL to Step/Direction controller, this can be abased on a UNO, MEGA, STM or other microcontroller on a a shield/Cape or connected via USB or serial.
The PI is very good at providing the user interface (See OCTOPrint or Pronterface for example of 3D printer solutions... still GCODE) but the microcontroller is much better at the FAST step/direction pulse generation and timing required to move the steppers smoothly, there just not so good at translating a circle smoothly into step and direction for example, so the PI in the case of CNC machine is pacing the feed of GCode to the controller and also pre processing the GCode to simplify the arcs, circles and other complex moves into simpler sets the controller can easily deal with, this is the normal and in my opinion better approach.
So technically the answer is yes but with caveats, the examples given above are for a wee little CNC / Laser engraver, almost every successful RPI based solution involves using a separate GRBL to Step/Direction controller, this can be abased on a UNO, MEGA, STM or other microcontroller on a a shield/Cape or connected via USB or serial.
The PI is very good at providing the user interface (See OCTOPrint or Pronterface for example of 3D printer solutions... still GCODE) but the microcontroller is much better at the FAST step/direction pulse generation and timing required to move the steppers smoothly, there just not so good at translating a circle smoothly into step and direction for example, so the PI in the case of CNC machine is pacing the feed of GCode to the controller and also pre processing the GCode to simplify the arcs, circles and other complex moves into simpler sets the controller can easily deal with, this is the normal and in my opinion better approach.
