Arduino Example Code – Motor Forward/Reverse & Stop

Hardware Preparation

• DFR0654 FireBeetle 2 ESP32-E ×1
• DFR1277 N20 UART motor ×1

Software Preparation

• Download and install Arduino IDE: Download Arduino IDE
• Download and install the DFRobot_N20SerialMotor library: Download DFRobot_N20SerialMotor library
• Download and install the DFRobot_RTU library: Download DFRobot_RTU Library
• Library Installation Guide: View Installation Guide

Wiring Diagram

Connection Description:

Sample Code

#include "DFRobot_N20SerialMotor.h"
/*
 * ESP32‑E Wiring:
 * N20 motor module VCC  → 5V
 * N20 motor module GND  → GND
 * N20 motor module RX   → ESP32 GPIO25 (Serial1‑TX)
 * N20 motor module TX   → ESP32 GPIO26 (Serial1‑RX)
 */
#define MOTOR_ADDR 1
#define MOTOR_BAUD 9600
// Use ESP32 hardware Serial1
DFRobot_N20SerialMotor motor(MOTOR_ADDR, &Serial1);

void setup()
{
  Serial.begin(115200);
  // Serial1: Baud rate 9600, 8N1, TX=25, RX=26
  Serial1.begin(MOTOR_BAUD, SERIAL_8N1, 25, 26);
  delay(1000);
  Serial.println();
  Serial.println(F("========================================"));
  Serial.println(F("  DFRobot N20 Serial Motor"));
  Serial.println(F("  ESP32‑E Single Motor Control"));
  Serial.println(F("========================================"));
  // Motor initialization, retry loop on failure
  while (motor.begin() != 0) {
    Serial.println(F("[ERROR] Motor init failed, retrying..."));
    delay(1000);
  }
  Serial.print(F("[OK] Motor initialized (Modbus addr: "));
  Serial.print(MOTOR_ADDR);
  Serial.println(F(")"));
  Serial.println(F("Starting speed control loop..."));
  Serial.println();
}

void loop()
{
  Serial.println(F("-> Speed 200"));
  motor.setSpeed(200);
  delay(2000);
  Serial.println(F("-> Stop"));
  motor.setSpeed(0);
  delay(2000);
  Serial.println(F("-> Speed -200"));
  motor.setSpeed(-200);
  delay(2000);
  Serial.println(F("-> Stop"));
  motor.setSpeed(0);
  delay(2000);
  Serial.println();
}

Result

Compile and upload the code, then open the Serial Monitor (Baud rate: 115200). After successful communication initialization, the motor cycles through forward rotation for 2s, stop for 2s, reverse rotation for 2s, stop for 2s. Control logs are printed simultaneously via serial port, as shown in the figure below.