Romeo BLE V1 - Need help with code

Hello,

I have this code and I can't make my Romeo V1 change speed. However I need help. How do I fix the code to be able to change speed.

I've enabled the code labeled ENA and ENB but nothing happens. I've removed the comment slashes but nothing happens when I change 255 to 100.

Any thoughts?

// Code for use with the DFRobot Romeo BLE V1 - motor controller for 2 DC motors - via usb

// Make sure DC motor polarity matches with motor terminal polarity on board + -


const int IN1 = 4; //One side motor 1
const int IN2 = 5;

const int IN3 = 6; //One side motor 2
const int IN4 = 7;



//const int ENA = 9;
//const int ENB = 3;


void setup() {

pinMode (IN1, OUTPUT);
pinMode (IN2, OUTPUT);

pinMode (IN3, OUTPUT);
pinMode (IN4, OUTPUT);


//pinMode (ENA, OUTPUT);
//pinMode (ENB, OUTPUT);


}

void loop() {


delay(5000);

//analogWrite(ENA, 100);
//analogWrite(ENB, 100);

digitalWrite(IN1, LOW); // Forwards
digitalWrite(IN2, HIGH);

digitalWrite(IN3, HIGH);
digitalWrite(IN4, LOW);

delay(3000);

//--------------------------------------------------

//STOP

//analogWrite(ENA, 255);
//analogWrite(ENB, 255);

digitalWrite(IN1, LOW);
digitalWrite(IN2, LOW);

digitalWrite(IN3, LOW);
digitalWrite(IN4, LOW);

delay(2000);

//------------------------------------------------

//analogWrite(ENA, 100); //Backwards
//analogWrite(ENB, 100);

digitalWrite(IN1, HIGH);
digitalWrite(IN2, HIGH);

digitalWrite(IN3, HIGH);
digitalWrite(IN4, HIGH);


delay(3000);

//--------------------------------------------------

//STOP

//analogWrite(ENA, 255);
//analogWrite(ENB, 255);

digitalWrite(IN1, LOW);
digitalWrite(IN2, LOW);

digitalWrite(IN3, LOW);
digitalWrite(IN4, LOW);

delay(2000);

//--------------------------------------------------

//Turn RIGHT

//analogWrite(ENA, 255);
//analogWrite(ENB, 255);

digitalWrite(IN1, HIGH);
digitalWrite(IN2, HIGH);

digitalWrite(IN3, HIGH);
digitalWrite(IN4, LOW);

delay(2000);


//--------------------------------------------------

//STOP

//analogWrite(ENA, 255);
//analogWrite(ENB, 255);

digitalWrite(IN1, LOW);
digitalWrite(IN2, LOW);

digitalWrite(IN3, LOW);
digitalWrite(IN4, LOW);

delay(2000);

//--------------------------------------------------

//Turn LEFT

//analogWrite(ENA, 255);
//analogWrite(ENB, 255);

digitalWrite(IN1, LOW);
digitalWrite(IN2, HIGH);

digitalWrite(IN3, HIGH);
digitalWrite(IN4, HIGH);

delay(2000);



//--------------------------------------------------

//STOP

//analogWrite(ENA, 255);
//analogWrite(ENB, 255);

digitalWrite(IN1, LOW);
digitalWrite(IN2, LOW);

digitalWrite(IN3, LOW);
digitalWrite(IN4, LOW);

delay(2000);

}