Axis Cloning

Overview

Many hobby gantry type CNC machines use 2 motors on Y axis. This prevent the bridge, that holds X and Z axes from driving from one side.

Rabbit Grbl can help with this because any axis can use 2 motors.

Axis Cloning Step & Direction Pins Configuration

You need to define a separate step and Direction pin for each motor, in you machine configuration file.
Use the axis letter for one of the motors and the axis letter plus a 2 for the other one.

Example:

#define Y_STEP_PIN              GPIO_NUM_25
#define Y2_STEP_PIN             GPIO_NUM_27

#define Y_DIRECTION_PIN         GPIO_NUM_26
#define Y2_STEP_PIN             GPIO_NUM_13