If you are thinking about using the GRBL Breakout Board/Shield CNC Design Ltd you might be uncomfortable wiring it up without having a clear idea of what is on the board. Especially as it doesn't come with anything more that a hookup diagram. For those reasons you might find the attached schematic helpful.
If you any errors please post to let me know- thanks.
I have a break-out board that came with the equipment.It failed and I replaced it with Arduino Uno/v3 sheild. But I control the spindle motor outside the board and just on/off type of control. No speed control
How do I control the DC motor of the spindle?
Do I need a dc driver or a simple transistor circut will do?