/*
 * Lesson 109-5: Controlling Speed of a motor using a Variable Resistor (potentiometer) and using a Start/Stop push button with Arduino.
 *
 * Generates output DC Voltage from 0 to 5.5V or lower. If the power supply
 * is 3.3V, then the maximum voltage is 3.3V.
 * We can set the voltage using 3 push buttons.
 * Button1 to increase
 * Button2 to decrease
 * Button3 to multiply the increment/decrement by 100 or whatever value
 * you see in the code
 *
 * Watch Video instruction for this code: https://youtu.be/j_BwZT9z-0g
 *
 * Projects in this video: https://youtu.be/j_BwZT9z-0g
 * Project 1: Output 0 to 5V or 0 to 3V depending on which kind of power source you use for the module. The output is shown on a digital multimeter.
 * Project 2: Serial command to set voltage
 * Project 3: PWM duty cycle to Voltage converter
 * Project 4: Using two MCP4725 DAC modules
 * Project 5 (this project): Using Push buttons to set voltage on LCD
 *
 * Written by Ahmad Shamshiri
 * Sep 27, 2022
 * www.Robojax.com
 *
 *
 * This code is part of the Arduino Step by Step Course which starts here:  https://youtu.be/-6qSrDUA5a8
 *
 * For the library for this code, visit http://robojax.com/
 *
 * If you found this tutorial helpful, please support me so I can continue creating
 * content like this. Make a donation using PayPal by credit card: https://bit.ly/donate-robojax
 *
 *
 * 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/>.
 *
 * Based on the Adafruit MCP4725 Library
 * ----> http://www.adafruit.com/products/935
 *
 * Adafruit invests time and resources providing this open source code,
 * please support Adafruit and open-source hardware by purchasing
 * products from Adafruit!
 */



#include <Wire.h>
#include <Adafruit_MCP4725.h>
const int refV = 4652;//reference voltage. see video for details

Adafruit_MCP4725 dac;
int mV =1356;//default value
float V;

#include <LiquidCrystal_I2C.h>
// Set the LCD address to 0x3f(green) for a 20 chars and 4 line display
int displayChars =16;//number of characters of display 16 or 20
int displayRows=2;//number of row of dispaly 2 or 4

const uint8_t PUSHBUTTON_PIN_1 =2;
const uint8_t PUSHBUTTON_PIN_2 =3;
const uint8_t PUSHBUTTON_PIN_3 =4;

 
const int incrementValue=15;//10mv
const int incrmentFast = 100;//
boolean showVolt=true;//false=millivolt, true=Volt


bool valueUpdate = false;

bool fastIncrementSet=false;
int newIncrementValue =0;
  //see video for details https://youtu.be/j_BwZT9z-0g
  //get more code from www.Robojax.com 
LiquidCrystal_I2C lcd(0x3f, displayChars, displayRows);


void setup(void) {
  Serial.begin(9600);
  Serial.println("MCP4725 by Robojax");
  pinMode(PUSHBUTTON_PIN_1, INPUT_PULLUP);
  pinMode(PUSHBUTTON_PIN_2, INPUT_PULLUP);  
  pinMode(PUSHBUTTON_PIN_3, INPUT_PULLUP);  
  
  //run i2C scanner to find out the I2C address and enter it below
    //see video for details https://youtu.be/j_BwZT9z-0g
  //get more code from www.Robojax.com 
  dac.begin(0x60);

  Serial.println("Output Voltage");
  // Turn on the blacklight and print a message.

  // initialize the LCD
  lcd.begin();  
  lcd.backlight();
  lcd.print("Robojax MCP4725");
  lcd.setCursor(0,1);
  lcd.print("Voltage: ");  
  lcd.setCursor(8,1);//start from charcter 9 of line 1  
  if(showVolt)
  {
    float Volt = (float) mV/1000;
    lcd.print(Volt);//print current voltage
    lcd.print("V");//print V   
  }else{
     lcd.print(mV);//print current voltage
    lcd.print("mV");//print mV    
  }

  setmV(mV);
  //delay(2000);
  //see video for details https://youtu.be/j_BwZT9z-0g
  //get more code from www.Robojax.com 
}

void loop(void) {
     pushButtons();
    //setmV(465);//set output to 465mV
//    Serial.print(mV);
//    Serial.println("mV");
//    delay(5000);
//    
//    setV(2.635);//set output to 2.6V
//    Serial.print(V, 3);
//    Serial.println("V");
//    delay(5000);
//    Serial.println();
//      clearCharFrom(8, 1);//clear the previous value (if updated) 
//      lcd.setCursor(8,1);//start from charcter 8 of line 1
//      lcd.print(mV);//print voltage
//      lcd.print("mV");//print mV
    //delay(100);
    if(valueUpdate)
    {
      printVoltage();
    }
    setmV(mV);
   //see video for details https://youtu.be/j_BwZT9z-0g
  //get more code from www.Robojax.com    
}



void pushButtons()
{
  int pb1 = digitalRead(PUSHBUTTON_PIN_1);
  int pb2 = digitalRead(PUSHBUTTON_PIN_2);
  int pb3 = digitalRead(PUSHBUTTON_PIN_3);

    //see video for details https://youtu.be/j_BwZT9z-0g
  //get more code from www.Robojax.com 
      if( (pb1 == LOW && pb3 == LOW ) || (pb2 == LOW && pb3 == LOW ) )
      {
        if(!fastIncrementSet)
        {
          newIncrementValue = incrementValue + incrmentFast;
          fastIncrementSet = true;
        }

      }else{
          newIncrementValue = incrementValue;
          fastIncrementSet = false;           
      }
  
  if(pb1 ==LOW){  

    if( (mV + newIncrementValue) <= refV )
    {
    
      mV =mV + newIncrementValue;

    }else{
      mV =refV;
    }
     valueUpdate = true;
  }else if(pb2 ==LOW){  
    if( (mV -newIncrementValue) >= 0)
    {
      mV =mV - newIncrementValue;
    }else{
      mV  =0;
   
    }
    valueUpdate = true;  
  }else{
    valueUpdate = false;  
  }

 delay(50);
}//

void printVoltage()
{
    //see video for details https://youtu.be/j_BwZT9z-0g
  //get more code from www.Robojax.com 
      clearCharFrom(8, 1);//clear the previous value (if updated) 
      lcd.setCursor(8,1);//start from charcter 8 of line 1
      if(showVolt)
      {
        float volt= (float)mV/1000.0;
        lcd.print(volt);//print voltage
        lcd.print("V");//print V  
      }else{
        lcd.print(mV);//print voltage
        lcd.print("mV");//print mV        
      }

}





/*
 * setmV()
 * sets mV value such as 35mV or 2654mV (2.654V)
 * Written Sep 25, 2022
 * by Ahmad Shamshiri www.Robojax.com
 */
void setmV(int d)
{
  
    mV =d;
    dac.setVoltage(map(d, 0, refV, 0, 4095), false);

}


/*
 * setV()
 * sets Voltage value in volts such as 3.764
 * Written Sep 25, 2022
 * by Ahmad Shamshiri www.Robojax.com
 */
void setV(float d)
{
    V = d;
    dac.setVoltage( map((d *1000), 0, refV, 0, 4095), false);

}  



void clearCharFrom(int c, int row)
{
    //see video for details https://youtu.be/j_BwZT9z-0g
  //get more code from www.Robojax.com 

    for(int i=c; i<displayChars; i++)
    {
      lcd.setCursor(i,row);//start from charcter 8 of line 1
      lcd.print(" ");
    }//for loop


  
}//clearCharFrom()