/*
push button usage as interrupt
timer for idle mode as interrupt

button updates a counter, that runs a switchcase.
each feature their own segment
*/
#define F_CPU 8000000UL //8mhz Internal -U lfuse:w:0xe4:m -U hfuse:w:0x99:m 
#include <LiquidCrystal.h>
#include <avr/sleep.h>

const int numRows = 2;
const int numCols = 16;
const byte BUTTON = 25;
volatile int var = 0;
const byte voltage = 30;
const byte beePin = 29;
const byte resistor = 28;
const byte gatevcc = 27;
const byte ReadPin = 26;
const byte AmpSig = 24;
const byte Discharge = 4;
const byte Charge = 3;
const int squackPin = 12;
LiquidCrystal lcd(18, 19, 20,21,22,23);
int R2 = 1000000;
int R1 = 5000000;
int R3 = 190000;
int VIN = 5;
int mVperAmp = 185;
double Voltage = 0;
double VRMS = 0;
double AmpsRMS = 0;
/* Interrupt Service Routine (ISR)
void switchPressed ()
{
  if (digitalRead (BUTTON) == HIGH)
var++;
    //300 second timer for sleep, 
}  // end of switchPressed*/
/*//void snore(int timer)
void snore()
            {
          lcd.display();
          lcd.clear();
          lcd.setCursor(0,0);
 //   attachInterrupt (digitalPinToInterrupt (BUTTON), switchPressed, CHANGE);  // attach interrupt handler
          lcd.print("Sleep in 10");
      }*/
float getVPP(int sensorIn)
{
  float result;
  
  int readValue;             //value read from the sensor
  int maxValue = 0;          // store max value here
  int minValue = 1024;          // store min value here
  
   uint32_t start_time = millis();
   while((millis()-start_time) < 250) //sample for 0.25 Sec
   {
       readValue = analogRead(sensorIn);
       // see if you have a new maxValue
       if (readValue > maxValue) 
       {
           /*record the maximum sensor value*/
           maxValue = readValue;
       }
       if (readValue < minValue) 
       {
           /*record the maximum sensor value*/
           minValue = readValue;
       }
   }
   
   // Subtract min from max
   result = ((maxValue - minValue) * 5.0)/1024.0;
      
   return result;
 }
void shortc()
      {
          lcd.display();
          lcd.clear();
          lcd.setCursor(0,0);
          lcd.print("BEEP");
          pinMode(beePin, INPUT );
          analogWrite(squackPin,0); 
          digitalWrite(gatevcc,HIGH);
          /*while (analogRead(beePin) == LOW)
          {
          analogWrite(squackPin,50);

          } */
          lcd.setCursor(0,1);
          lcd.print(analogRead(beePin));
          delay(100);
          analogWrite(squackPin,0); 


      }
void res()
            {
          lcd.display();
          lcd.clear();
          lcd.setCursor(0,0);
          lcd.print("Resistor");
  // read the input voltage on the resistance terminals
  int resValue = getVPP(resistor);
  // convert the reading to voltage. 
  //float resVolt = resValue * (5.0 / 1023.0);
  float Resistor = R3*(1/((VIN-resValue)-1));
          lcd.setCursor(0,1);
          lcd.print(Resistor);
          lcd.print(" Ohm");
          delay(100);
      }
void capacitor()
            {
          lcd.display();
          lcd.clear();
          lcd.setCursor(0,0);

          lcd.print("Capacitor");
          lcd.setCursor(0,1);
          lcd.print(analogRead(ReadPin));
          delay(100);
      }
void current()
            {
          lcd.display();
          lcd.clear();
          lcd.setCursor(0,0);
          lcd.print("Current");
          Voltage = getVPP(AmpSig);
          VRMS = (Voltage/2.0) *0.707; 
          AmpsRMS = (VRMS * 1000)/mVperAmp;
          lcd.setCursor(0,1);
          lcd.print(AmpsRMS);
          lcd.print(" Amps RMS");
          delay(100);
      }
void volt()
            {
          lcd.display();
          lcd.clear();
          lcd.setCursor(0,0);
          lcd.print("Voltage ");
          lcd.setCursor(0,1);
          int voltValue = getVPP(voltage);
          // Convert the analog reading (which goes from 0 - 1023) to a voltage (0 - 5V):
          //float Vout = voltValue * (5.0 / 1023.0);
          float Vin = (R2/(R1+R2))/voltValue;
          
          lcd.setCursor(0,1);
          lcd.print("Vin ");
          lcd.print(Vin);
          lcd.print(" V");
          delay(100);
      }


void setup ()
{

  lcd.begin(numCols, numRows);
  pinMode(BUTTON, INPUT);
  pinMode(AmpSig,INPUT);
  pinMode(ReadPin, INPUT);
  pinMode(resistor, INPUT);
  pinMode(voltage, INPUT);
  pinMode(beePin, INPUT);
  pinMode(squackPin, OUTPUT);
  pinMode(gatevcc, OUTPUT);
  //Serial.begin(9600);
  lcd.print("FabLab Oulu");
  lcd.setCursor(0,1);
  lcd.print("Mikko Toivonen");
  delay(1000);
}  // end of setup



void loop ()
{
  if (digitalRead (BUTTON) == LOW)
  {
var++;
  }
//lcd.display();
delay(175);
//lcd.print(var);

 switch (var) {
    case 1:
      shortc();//short circuit checking
      break;     
    case 2:
      volt();// voltage measurement
      break;
    case 3:
      res();// resistor measurement
      break;
    case 4:
      current();// current measurement
      break;
    case 5:
      capacitor();//capacitor measurement 
/*      break;  
          case 6:

      snore();//putting the chip to sleep
      break; */         
    default:
            {
          lcd.display();
          lcd.clear();
          lcd.setCursor(0,0);
          lcd.print("Press Button");
          var = 0;
      }

    //10 second timer for sleep
    break;

  }
}