## Wiring Procedure

The electronic control system of the CNC Foam Cutter Machine was built using an Arduino Uno, CNC Shield V3, A4988 stepper motor drivers, NEMA 17 stepper motors, and a 12V DC power supply. The CNC Shield was mounted directly on top of the Arduino Uno, providing a compact and organized platform for motor control.

The Arduino Uno was connected to the computer through a USB cable. This USB connection was used for uploading the GRBL firmware and for communication between the computer and the machine through Universal G-Code Sender (UGS). During operation, the Arduino receives G-code commands from UGS and generates STEP and DIRECTION signals required for motor movement.

The CNC Shield V3 was stacked directly on the Arduino Uno. The shield simplifies wiring by providing dedicated sockets for A4988 motor drivers and terminal connections for the stepper motors. The X-axis and Y-axis motors were connected to their respective motor output terminals on the CNC Shield.

A4988 stepper motor drivers were inserted into the X-axis and Y-axis driver sockets of the CNC Shield. Before powering the system, the orientation of the drivers was carefully verified to avoid damage. Heat sinks were attached to the A4988 modules to improve heat dissipation during operation.

A 12V DC power adapter was used as the main power source for the machine. The adapter was plugged into an extension board connected to the AC mains supply. Instead of using a DC barrel jack, the positive and negative output wires from the power adapter were connected directly to the power input screw terminal of the CNC Shield.

The red wire from the power supply was connected to the positive (+) terminal of the CNC Shield power input. The black wire from the power supply was connected to the negative (GND) terminal of the CNC Shield power input. These connections provide motor power to the A4988 drivers and stepper motors.

Once power is supplied, the CNC Shield distributes the 12V input voltage to the A4988 motor drivers through the VMOT and GND lines. The A4988 drivers then use this power to energize the coils of the stepper motors according to the STEP and DIR signals received from the Arduino.

Each NEMA 17 stepper motor contains two separate coils. The motor wires were connected to the corresponding output terminals of the CNC Shield. Proper coil pairing was verified before operation to ensure smooth motor rotation and accurate positioning.

The microstepping configuration jumpers were installed beneath each A4988 driver on the CNC Shield. These jumpers determine the stepping resolution and help achieve smoother machine movement.

The current limit of each A4988 driver was adjusted using the onboard potentiometer. A multimeter was used to measure the reference voltage (Vref), and the adjustment screw was carefully rotated until the desired current limit was achieved. Proper current limiting prevents overheating of both the motor and driver.

After completing all wiring connections, the Arduino Uno was connected to the computer and Universal G-Code Sender (UGS) was launched. The GRBL controller was detected through the correct COM port, and communication was established successfully.

Manual jogging operations were then performed using UGS to verify motor movement. The X-axis and Y-axis motors responded correctly to the control commands, confirming proper wiring of the power supply, CNC Shield, A4988 drivers, and stepper motors.

This wiring configuration enabled the Arduino Uno to control machine movement through GRBL firmware while the CNC Shield and A4988 drivers supplied the required motor power for accurate CNC operation.