++
/*
 * 
 *   L293D motor shield library
 * Original Adafruit-Motor-Shield-library
 * Library URL: https://github.com/adafruit/Adafruit-Motor-Shield-library
 * 
 * This code is to control 4 DC motors in both CW and CCW directions.
 * I have modified the code to allow you to better understand how to control DC motors.
 * 
 * Learn how to use the L293D chip without the shield: https://youtu.be/akQoGNUzhHI
 *  * 
 * Written by Ahmad Shamshiri on Feb 11, 2021 in Ajax, Ontario, Canada
 * www.Robojax.com
 * 
  * 
 * This code is "AS IS" without warranty or liability. Free to be used as long as you keep this note intact.
 * This code has been downloaded from Robojax.com
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.
   
*/
#include <AFMotor.h>

AF_DCMotor m1(1);//define motor 1 as m1
AF_DCMotor m2(2);//define motor 2 as m2
AF_DCMotor m3(3);//define motor 3 as m3
AF_DCMotor m4(4);//define motor 4 as m4


void setup() {
  Serial.begin(9600);           // set up Serial library at 9600 bps
  Serial.println("Robojax Motor test!");

  // initial state of motor; turn on motor
  m1.setSpeed(0);//motor 1 is turned off; to turn on, change 0 to 255
  m2.setSpeed(0);//motor 2 is turned off  
  m3.setSpeed(0);//motor 3 is turned off 
  m4.setSpeed(0); //motor 4 is turned off 
}

void loop() {
  uint8_t i;
  
  Serial.println("Motor 1 FORWARD 100% speed");
  m1.run(FORWARD);
  m1.setSpeed(speed(100));
  Serial.println("m4 FORWARD 100%");
 m4.run(FORWARD);
 m4.setSpeed(speed(100));  
  delay(3000);
  

  
  m1.run(RELEASE);
  Serial.println("M1 RELEASE");
 m4.run(RELEASE);
  Serial.println("m4 RELEASE");  
  delay(3000); 

  

  Serial.println("M1 BACKWARD 80%");
  m1.run(BACKWARD );
  m1.setSpeed(speed(80));
  Serial.println("m4 BACKWARD 60%");
 m4.run(BACKWARD );
 m4.setSpeed(speed(60));


  delay(3000);

  
 delay(3000);
  m1.run(RELEASE);
  Serial.println("M1 RELEASE");
  m4.run(RELEASE);
  Serial.println("m4 RELEASE");  
  delay(3000);   
  Serial.println("=============");
}

/*
 * Get percentage value (0 to 100%) and 
 * converts it to 0 to 255, which is the motor speed used by Arduino.
 * Written by Ahmad Shamshiri on Feb 12, 2021
 */
int speed(int b)
{
  return map(b, 0, 100, 0, 255);
}