Hướng dẫn sử dụng mạch cầu H-Bridge Motor Driver [L293D] để làm động cơ xe

Hướng dẫn sử dụng mạch cầu H-Bridge Motor Driver [L293D] để làm động cơ xe.
* Mã code
#define E1 10  // Enable Pin for motor 1
#define E2 11  // Enable Pin for motor 2

#define I1 8  // Control pin 1 for motor 1
#define I2 9  // Control pin 2 for motor 1
#define I3 12  // Control pin 1 for motor 2
#define I4 13  // Control pin 2 for motor 2
int speed =255;

void setup() {
    Serial.begin(9600);
    pinMode(E1, OUTPUT);
    pinMode(E2, OUTPUT);

    pinMode(I1, OUTPUT);
    pinMode(I2, OUTPUT);
    pinMode(I3, OUTPUT);
    pinMode(I4, OUTPUT);
     
}
//--------------
// motor 1
void E1_Dung() {
 digitalWrite(E1, LOW);
}
void E1_Tien(int speed) { //speed: từ 0 - MAX_SPEED
analogWrite(E1, speed); // Run in full speed
     digitalWrite(I1, HIGH);
     digitalWrite(I2, LOW);
}

void E1_Lui(int speed) {
analogWrite(E1, speed);  // Run in full speed
    digitalWrite(I1, LOW);
    digitalWrite(I2, HIGH);
}
//--------------
// motor 2
void E2_Dung() {
   digitalWrite(E2, LOW);
}
void E2_Tien(int speed) { //speed: từ 0 - MAX_SPEED
    analogWrite(E2, speed); // Run in full speed
  digitalWrite(I3, HIGH);
    digitalWrite(I4, LOW);
}
void E2_Lui(int speed) {
    analogWrite(E2, speed);  //  Run in full speed
    digitalWrite(I3, LOW);
    digitalWrite(I4, HIGH);
}

//-------------------
void loop() {
      int state = Serial.read();
      if(state>0)
      switch (state) {
      case '1':// Tien
       E1_Tien(speed);
      E2_Tien(speed);
       Serial.println("Tien");
       break;
      case '2':// Lui
        E1_Lui(speed);
       E2_Lui(speed);
        Serial.println("Lui");
        break;
      case '3'://Dung
       E1_Dung();
      E2_Dung();
        Serial.println("Dung");
       break;
      case '4':// Trai
       E1_Dung();
       E2_Tien(speed);
        Serial.println("Quay Trai");
      break;
      case '5':// Phai
      E1_Tien(speed);
      E2_Dung();
        Serial.println("Quay Phai");
      break;
      default:
      break;
      }
}
* Mô hình mạch

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