/www.elegoo.com
//2016.12.12

/************************
Exercise the motor using
the L293D chip
************************/

#define ENABLE 5
#define DIRA 3
#define DIRB 4

int i;
 
void setup() {
  //---set pin direction
  pinMode(ENABLE,OUTPUT);
  pinMode(DIRA,OUTPUT);
  pinMode(DIRB,OUTPUT);
  Serial.begin(9600);
}

void loop() {
   Serial.println("PWM full then slow");
  //---PWM example, full speed then slow
  analogWrite(ENABLE,25); //enable on
  digitalWrite(DIRA,HIGH); //one way
  digitalWrite(DIRB,LOW);
  delay(3000);
  analogWrite(ENABLE,50); //half speed
  delay(3000);
  analogWrite(ENABLE,75); //half speed
  delay(3000);
}