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Lesson 49: Using L293D with Arduino to control drive a DC Motor

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  • L293D Motor Driver Datasheet (pdf)
  • Part 5: DC Motors

    In this lesson we learn how to use L293D Motor driver to drive a DC motor using Arduino code. Please watch the video for full details.

    AliExpress.com Product - 5pcs/lot L293D L293 DIP-16 In Stock
    
     /*
     * Robojax Arduino Step By Step Course
     * Part 4: Temperature Sensors
     * Lesson 47: Using Max6675 as Thermostat with relay
     * 
     * This is Arduino code to measure MAX6675 Thermocoupler K-Type sensor
     * and control realy as Heater or cooler
    
       Please watch video instruction here https://youtu.be/yJYXfaU9J34
       Introduction to MAX6675 video is https://youtu.be/A55QNx6kCoo
     This code is available at http://robojax.com/course1/?vid=lecture47
    
     
    Course worth of $200 with over 150 lectures Free On  YouTube Watch it here http://robojax.com/L/?id=338
    Get the code for the course: http://robojax.com/L/?id=339  
    
     * Written by Ahmad Shamshiri on May 20, 2020 at in Ajax, Ontario, Canada
     * in Ajax, Ontario, Canada. www.robojax.com
     * 
     * Library from : // www.ladyada.net/learn/sensors/thermocouple
     * 
    
    or make donation using PayPal http://robojax.com/L/?id=64
    
     *  * 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 download 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 "max6675.h"
    //Robojax.com heater/cooler with MAX6675 Thermocoupler
    int GNDpin = 2;
    int VCCpin =3;
    int thermoCLK = 4;
    int thermoCS = 5;
    int thermoDO = 6;
    MAX6675 thermocouple(thermoCLK, thermoCS, thermoDO);
    
    
    const int relayPin =8;
    const int relayON = LOW;// do not change
    const int relayOFF = HIGH; //do not chage 
    int relayState = relayOFF;//initial state of relay
    
    const int TEMPERATURE_UNIT =1;//1=Celsius, 2=Fahrenheit, 3=Keliven
    const float START_TEMPERATURE = 80.0;//unit above
    const float STOP_TEMPERATURE = 100.0;//unit above
    const int CONTROL_TYPE = 1;// 1= heater, 2=cooler
    float temperature;
    
    void setup() {
      //Robojax.com heater/cooler with MAX6675 Thermocoupler
      //free course YouTube Watch it here http://robojax.com/L/?id=338
      Serial.begin(9600);
      Serial.println("MAX6675 test with relay");
      // use Arduino pins 
      pinMode(relayPin, OUTPUT);//pin for relay
      digitalWrite(relayPin, relayState);
      
      pinMode(VCCpin, OUTPUT);
      digitalWrite(VCCpin, HIGH);
    
      pinMode(GNDpin, OUTPUT);
      digitalWrite(GNDpin, LOW);
    
      // wait for MAX chip to stabilize
      delay(500);
    //Robojax.com heater/cooler with MAX6675 Thermocoupler  
    }
    
    void loop() {
      //free course YouTube Watch it here http://robojax.com/L/?id=338  
      //Robojax.com heater/cooler with MAX6675 Thermocoupler
       readTemperature();
       printTemperature();
       loadControl(); 
       if(temperature >=89.5)
       {
        ///
       }
       delay(1000);
    //Robojax.com heater/cooler with MAX6675 Thermocoupler   
    }//loop
    
    
    
    /*
     * loadControl()
     * @brief controls the load based 
     * @param state can be either : relayON or relayOFF
    
     * @return returns none
     * Written by Ahmad Shamshiri for robojax.com
     * on May 20, 2020 at 15:23 in Ajax, Ontario, Canada
     */
    void loadControl()
    {
        //free course YouTube Watch it here http://robojax.com/L/?id=338
    //Robojax.com heater/cooler with MAX6675 Thermocoupler  
         // Serial.print("Start: ");
         // Serial.print(START_TEMPERATURE);
         // Serial.print(" Stop: ");
          //Serial.println(STOP_TEMPERATURE);      
      if(CONTROL_TYPE ==1)
      {
        if(START_TEMPERATURE >= temperature && STOP_TEMPERATURE >=temperature)
        {
          relayControl(relayON);
        }
        if(STOP_TEMPERATURE <=temperature)
        {
          relayControl(relayOFF);
        }
      }else{
        if(START_TEMPERATURE >= temperature && STOP_TEMPERATURE >=temperature)
        {
          relayControl(relayOFF);
        }
        if(STOP_TEMPERATURE <=temperature)
        {
          relayControl(relayON);
        }
      }
        
    //Robojax.com heater/cooler with MAX6675 Thermocoupler
    }//loadControl()
    
    
    /*
     * relayControl(int state))
     * @brief turns the relay ON or OFF
     * @param state is "relayON" or "relayOFF" defined at the top of code
     * @return returns none
     * Written by Ahmad Shamshiri for robojax.com
     * on May 20, 2020 at 15:23 in Ajax, Ontario, Canada
     */
    void relayControl(int state)
    {
        //free course YouTube Watch it here http://robojax.com/L/?id=338
      //Robojax.com heater/cooler with MAX6675 Thermocoupler
      if(state ==relayON)
      {
        digitalWrite(relayPin, relayON);
        Serial.println("Relay ON");   
      }else{
       digitalWrite(relayPin, relayOFF);    
        Serial.println("Relay OFF");   
      }
      //Robojax.com heater/cooler with MAX6675 Thermocoupler  
      //free course YouTube Watch it here http://robojax.com/L/?id=338
    }//relayControl()
    
    
    /*
     *  readTemperature()
     * @brief reads the temperature based on the TEMPERATURE_UNIT
     * @param average temperature
    
     * @return returns one of the values above
     * Written by Ahmad Shamshiri for robojax.com
     * on May 20, 2020 at 15:23 in Ajax, Ontario, Canada
     */
    void readTemperature()
    {
        //free course YouTube Watch it here http://robojax.com/L/?id=338
     //Robojax.com heater/cooler with MAX6675 Thermocoupler 
    
      if(TEMPERATURE_UNIT ==2)
       {
       temperature = thermocouple.readFahrenheit();//convert to Fahrenheit 
       }else if(TEMPERATURE_UNIT ==3)
       {
        temperature = thermocouple.readCelsius() + 273.15;//convert to Kelvin
       }else{
        temperature = thermocouple.readCelsius();// return Celsius
       }    
     //Robojax.com heater/cooler with MAX6675 Thermocoupler 
    }// readTemperature()
    
    /*
     * printTemperature()
     * @brief prints  temperature on serial monitor
     * @param charact type
     * @param "type" is character
     *     C = Celsius
     *     K = Keliven
     *     F = Fahrenheit
     * @return none
     * Written by Ahmad Shamshiri for robojax.com
     * on May 08, 2020 at 02:45 in Ajax, Ontario, Canada
     */
    void printTemperature()
    {
        //free course YouTube Watch it here http://robojax.com/L/?id=338
    //Robojax.com heater/cooler with MAX6675 Thermocoupler
       Serial.print(temperature);
        printDegree();    
      if(TEMPERATURE_UNIT ==2)
       {
         Serial.print("F");
        }else if(TEMPERATURE_UNIT ==3)
       {
         Serial.print("K");
       }else{
         Serial.print("C");
       }    
      Serial.println();
    //Robojax.com heater/cooler with MAX6675 Thermocoupler  
    }//printTemperature()
    
    /*
     * @brief prints degree symbol on serial monitor
     * @param none
     * @return returns nothing
     * Written by Ahmad Shamshiri on July 13, 2019
     * for Robojax Tutorial Robojax.com
     */
    void printDegree()
    {
        //free course YouTube Watch it here http://robojax.com/L/?id=338
        Serial.print("\xC2"); 
        Serial.print("\xB0");  
    }
    
       

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