A4988 Arduino CNC shield

BOM

• Arduino CNC Shield PCB
• 100uF 50v 8mm High Capacitors (493-3289-ND)
• Jumpers (A26228-ND)
• 8-Pin Female Headers(S7006-ND)
• Male Headers(A26514-40-ND)
• Tactile Switch (450-1650-ND)
• Screw Terminal 5mm (A97996-ND)
• Pololu Stepper Drivers . (Please note that the shield was designed to work with A4988 compatable polulu drivers)
• 10K pull-up resistors

Schematic

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  schematic

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  Board Layout

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  Board Layout 2

GRBL Software/Firmware

GRBL is opensource software that runs on an Arduino Uno that takes G-Code commands via Serial and turns the commands into motor signals.

The GRBL source Code is located here.

Assembly

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  How it looks finally

• For the M0-M2 configuration, set is low when no jumper connected and high when jumper connected, check on A4988 board configuration for this.
• A.STP and A.DIR is to copy/clone the motor setting from X, Y or Z axis to the fourth motor if you have.

First Run Debugging

• Check all the solderings to make sure all soldered well
• Adjust A4988 breakout board when necessary, and carefully install the A4988 driver board
• Connect external power to power up
• upload arduino firmware and test communication via serial port for gbrl, send demo G-code for testing all four axis.