CAN-Linked Rover

Two microcontrollers talking over a CAN bus. An ESP32 sends drive commands, and an Arduino Uno receives them and drives DC motors through an L298N H-bridge.

How it works

• The ESP32 acts as the primary brain and sends a drive command over CAN.
• The Arduino Uno receives it through an MCP2515 CAN module and sets the motor direction and speed.
• Direction is set with the L298N input pins, and speed is set with PWM on the enable pin.
• The ESP32 resends the command every 100 ms. If the Uno stops hearing commands for 300 ms, it stops the motor on its own.

Hardware

• ESP32
• Arduino Uno
• 2x MCP2515 CAN modules
• L298N motor driver
• DC motor

CAN message

• Bus speed: 500 kbps
• Message ID: 0x100
• Data (2 bytes): direction (0 stop, 1 forward, 2 reverse) and speed (0-255)

Wiring

Board	Connection	Pin
ESP32	CAN chip select	GPIO 5
ESP32	SPI (SCK, MISO, MOSI)	GPIO 18, 19, 23
Uno	CAN chip select	D10
Uno	SPI (SCK, MISO, MOSI)	D13, D12, D11
Uno	L298N enable (PWM)	D5
Uno	L298N IN1, IN2	D6, D7