#define BLYNK_NO_BUILTIN   // Disable built-in analog & digital pin operations

#include <ESP8266_Lib.h>
#include <BlynkSimpleShieldEsp8266.h>
// You should get Auth Token in the Blynk App.

char auth[] = "*********************************"; // put you blunk auth token here
// Your WiFi credentials.
// Set password to "" for open networks.
char ssid[] = "********"; // put your Wifi name here
char pass[] = "********"; // put your Password here

//Software Serial on Uno, Nano, Pro mini...
#include <SoftwareSerial.h>
SoftwareSerial EspSerial(9, 10); // RX, TX //Connect TX of ESP8266 to RX and RX of ESP8266 to TX of Software serial.
// Your ESP8266 baud rate:
ESP8266 wifi(&EspSerial);

#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define OLED_RESET 4
Adafruit_SSD1306 display(OLED_RESET);

float current=0;
float voltage=0;
void setup() 
{
pinMode(A0,INPUT);
pinMode(A1,INPUT);
display.begin(SSD1306_SWITCHCAPVCC, 0x3C);  // initialize with the I2C addr 0x3C (for the 128x32)
 
  display.display();
  EspSerial.begin(9600);
  delay(10);
  Blynk.begin(auth, wifi, ssid, pass);
 // Clear the buffer.
  display.clearDisplay();
  display.setTextSize(1);
  display.setCursor(0, 0);
  display.setTextColor(WHITE);

  
}

void loop() 
{
  // taking average for stable readings
for(int i=0; i<20;i++)
{
  current=current+analogRead(A1);
  voltage=voltage+analogRead(A0);
  delay(2); 
}
current=current/20;
current=(current*0.068); // calibration value will change depending upon the gain of Op Amp circuit and resistance of the shunt
if(current<0)
current=0;
voltage=voltage/20;
voltage=voltage*2.485; // calibration constant depends upon the voltage divider network
   
  display.setCursor(0, 0);
  display.print("Voltage: ");
  display.print(voltage);
  display.println(" V");
  display.setCursor(0, 10);
  display.print("Current: ");
  display.print(current);
  display.println(" A");
  display.setCursor(0, 20);
  display.print("Power: ");
  display.print(voltage*current);
  display.println(" W");
  
   display.display(); //you have to tell the display to...display
   delay(500);
   display.clearDisplay();
Blynk.virtualWrite(V5,voltage);
Blynk.virtualWrite(V6,current);
Blynk.virtualWrite(V7,voltage*current);
}