Documentation

// L298N - Drive 2 DC motors forward, backward, and stop
// Motor A: ENA=D9, IN1=D8, IN2=D7
// Motor B: ENB=D3, IN3=D5, IN4=D4

const int ENA = 9;
const int IN1 = 8;
const int IN2 = 7;
const int ENB = 3;
const int IN3 = 5;
const int IN4 = 4;

void setup() {
  pinMode(ENA, OUTPUT); pinMode(IN1, OUTPUT); pinMode(IN2, OUTPUT);
  pinMode(ENB, OUTPUT); pinMode(IN3, OUTPUT); pinMode(IN4, OUTPUT);
}

void setMotor(int enPin, int in1, int in2, int speed) {
  // speed: -255 (full back) .. 255 (full fwd). 0 = stop.
  digitalWrite(in1, speed > 0 ? HIGH : LOW);
  digitalWrite(in2, speed < 0 ? HIGH : LOW);
  analogWrite(enPin, abs(speed));
}

void loop() {
  setMotor(ENA, IN1, IN2, 200);   // Motor A forward ~80%
  setMotor(ENB, IN3, IN4, 200);   // Motor B forward ~80%
  delay(2000);

  setMotor(ENA, IN1, IN2, -150);  // Motor A reverse ~60%
  setMotor(ENB, IN3, IN4, -150);
  delay(2000);

  setMotor(ENA, IN1, IN2, 0);     // stop
  setMotor(ENB, IN3, IN4, 0);
  delay(1000);
}

// L298N on ESP32 - dual DC motors using LEDC PWM

const int ENA = 13, IN1 = 14, IN2 = 27;
const int ENB = 33, IN3 = 26, IN4 = 25;
const int PWM_FREQ = 20000, PWM_RES = 8;

void setup() {
  pinMode(IN1, OUTPUT); pinMode(IN2, OUTPUT);
  pinMode(IN3, OUTPUT); pinMode(IN4, OUTPUT);

  ledcAttach(ENA, PWM_FREQ, PWM_RES);
  ledcAttach(ENB, PWM_FREQ, PWM_RES);
}

void motor(int enPin, int in1, int in2, int speed) {
  digitalWrite(in1, speed > 0);
  digitalWrite(in2, speed < 0);
  ledcWrite(enPin, abs(speed));
}

void loop() {
  motor(ENA, IN1, IN2, 200); motor(ENB, IN3, IN4, 200); delay(2000);
  motor(ENA, IN1, IN2, -200); motor(ENB, IN3, IN4, -200); delay(2000);
  motor(ENA, IN1, IN2, 0);  motor(ENB, IN3, IN4, 0);  delay(1000);
}

# L298N on Raspberry Pi - drive 2 DC motors with PWM
# Install: pip install gpiozero

from gpiozero import Motor, PWMOutputDevice
from time import sleep

# gpiozero's Motor handles direction; we add PWM for speed
motor_a = Motor(forward=23, backward=24)
speed_a = PWMOutputDevice(12)

motor_b = Motor(forward=27, backward=22)
speed_b = PWMOutputDevice(13)

def drive(motor, speed_pin, speed):
    if speed > 0:
        motor.forward()
    elif speed < 0:
        motor.backward()
    else:
        motor.stop()
    speed_pin.value = abs(speed)

try:
    while True:
        drive(motor_a, speed_a, 0.8); drive(motor_b, speed_b, 0.8); sleep(2)
        drive(motor_a, speed_a, -0.6); drive(motor_b, speed_b, -0.6); sleep(2)
        drive(motor_a, speed_a, 0);   drive(motor_b, speed_b, 0);   sleep(1)
except KeyboardInterrupt:
    pass

# L298N on Raspberry Pi Pico - two DC motors

from machine import Pin, PWM
import time

ENA = PWM(Pin(2)); IN1 = Pin(3, Pin.OUT); IN2 = Pin(4, Pin.OUT)
ENB = PWM(Pin(7)); IN3 = Pin(5, Pin.OUT); IN4 = Pin(6, Pin.OUT)

ENA.freq(20000); ENB.freq(20000)

def motor(en, in1, in2, speed):
    # speed in -65535..65535
    in1.value(1 if speed > 0 else 0)
    in2.value(1 if speed < 0 else 0)
    en.duty_u16(min(abs(speed), 65535))

while True:
    motor(ENA, IN1, IN2,  50000); motor(ENB, IN3, IN4,  50000); time.sleep(2)
    motor(ENA, IN1, IN2, -40000); motor(ENB, IN3, IN4, -40000); time.sleep(2)
    motor(ENA, IN1, IN2,  0);     motor(ENB, IN3, IN4,  0);     time.sleep(1)