/* Dummy Load
Version 1.003
15/9/2024



*/
//
//  Includes-
#include <LiquidCrystal.h>
//
//
//
//
//
//
//
//  Declare variables
//
/* Display */
LiquidCrystal lcd(12, 11, 10, 9, 8, 7);




float LoadResistance;          //  Load resistance value determined from pin selection function reading pind D2-D4
float RawVoltage;              //  Analogue voltage read from top of load resistor in ADC counts.  Analogue voltage scaled down by 8 to fit Arduino ADC input range.  eg 40V p-p  becomes 5V  p-p
float UncalibratedVoltage;     //  RawVoltage scaled to 
int OhmSelectionPin4  = 2;            // Digital input pin 2 to select 4 ohm resistor- it will be high if selector switch isd set to 4 ohm load
float OhmRealValue4 = 3.99;              // Acual resistor value measured  eg 3.98ohms
int OhmSelectionPin8  = 3;            // Digital input pin 3 to select 8 ohm resistor- it will be high if selector switch isd set to 8 ohm load
float OhmRealValue8 = 7.99;              // Acual resistor value measured  eg 7.98ohms
int OhmSelectionPin15 = 4;            // Digital input pin 4 to select 15 ohm resistor- it will be high if selector switch isd set to 15 ohm load
float OhmRealValue15 = 14.99;            // Acual resistor value measured  eg 14.98ohms
float CurrentResistorValue=6.5;
int analogueVoltagePin = 0;
float peakToRMS = 0.70711;
float RMSVoltage;
float scaledVoltage;
float scaleVoltageADCFactor = 0.0390625;
float voltCalibratedVoltage;
float voltageCalibrationFactor = 0.48;   //use to test input voltage on Wokwi.com simulator
float freqCalibratedVoltage;
float frequencyCalibrationFactor = 0.99;

bool pinState4;
bool pinState8;
bool pinState15;

// Frequency stuff
int Htime;              //integer for storing high time
int Ltime;                //integer for storing low time
float Ttime;            // integer for storing total time of a cycle
float frequency;        //storing frequency
int FrequencyInputPin = 5;  //  D5 has the frequeny signal on it


//Values to put onscreen
float voltageDisplay;
float currentDisplay;
float resistanceDisplay;
float powerDisplay;
float frequencyDisplay;

void setup() {
  // put your setup code here, to run once:
  lcd.begin(16, 2);

  // Pin Assignments
  pinMode(OhmSelectionPin4, INPUT);       //  resistor selection pin
  pinMode(OhmSelectionPin8, INPUT);       //  resistor selection pin
  pinMode(OhmSelectionPin15, INPUT);      //  resistor selection pin
  pinMode(FrequencyInputPin,INPUT);       //  frequency Pin 



}

//  Functions Below-

void readVoltage ()
{
RawVoltage = analogRead(analogueVoltagePin);     // get adc counts
}

void scaleADCVoltage()
{
  scaledVoltage = RawVoltage * scaleVoltageADCFactor;   //  one ADC count equals  0.0390625 Volts  
}

void calibrateVoltage()
{
//freq
freqCalibratedVoltage = scaledVoltage * frequencyCalibrationFactor;
//voltage
voltCalibratedVoltage = freqCalibratedVoltage * voltageCalibrationFactor;  //r
}

void toRMSVoltage ()
{
RMSVoltage = voltCalibratedVoltage * peakToRMS;
}

void setDisplayVoltage ()

{
  voltageDisplay=RMSVoltage;
}


void calculateCurrent ()
{

  currentDisplay = RMSVoltage/CurrentResistorValue;
}


void readResistorSelection ()
{

    pinState4 = digitalRead(OhmSelectionPin4);
    pinState8 = digitalRead(OhmSelectionPin8);
    pinState15 = digitalRead(OhmSelectionPin15);


  if (pinState4 == HIGH) {resistanceDisplay = OhmRealValue4;}    //
  if (pinState8 == HIGH) {resistanceDisplay = OhmRealValue8;}
  if (pinState15 == HIGH) {resistanceDisplay = OhmRealValue15;}

 
}
void readFrequenccy ()
{
  Htime=pulseIn(FrequencyInputPin,HIGH);      //read high time
  Ltime=pulseIn(FrequencyInputPin,LOW);        //read low time
  Ttime = Htime+Ltime;
  frequency=1000000/Ttime;    //getting frequency with Ttime is in Micro seconds
  frequencyDisplay=frequency;
}


void writeValuesToLCD ()
{
  lcd.setCursor(0, 0);
  lcd.print(voltageDisplay);   // Works
  lcd.setCursor(6, 0);
  lcd.print("V");

  lcd.setCursor(10, 0);
  lcd.print(currentDisplay);  // works
  lcd.setCursor(15, 0);
  lcd.print("A");


  lcd.setCursor(0, 1);
  lcd.print(voltageDisplay * currentDisplay);   // works
  lcd.setCursor(6, 1);
  lcd.print("W");


  lcd.setCursor(10, 1);
  lcd.print(frequencyDisplay);    // works n
  lcd.setCursor(14, 1);
  lcd.print("Hz");



 delay (1000);
}




void loop() {
 // put your main code here, to run continuously:

  readFrequenccy ();

  readVoltage ();

  scaleADCVoltage ();  //Convert ADC Counts to voltage

  calibrateVoltage();  //placeholder function pending completed build and testing/calibration

  toRMSVoltage ();
  
  setDisplayVoltage ();

  readResistorSelection ();

  calculateCurrent ();

  writeValuesToLCD ();

  delay(100);
}