Ионисторы 4 фарада - Суперконденсаторы!

// Capacitance meter v1.1
// consists:
//    1) Arduino MEGA 2560
//    2) DS 3231 real time clock:   SCL, SDA, VCC, GND
//    3) Micro SD card reader SPI:  CS -> 53, SCK -> 52, MOSI -> 51, MISO -> 50, VCC, GND
//    4) analog voltage sensor:     VCC, GND, A0
//    5) analog current sensor:     VCC, GND, A1 (optional, for big discharge currents, not fully implemented yet)
//    6) 0.96" OLED 128x64 IIC display: SCL, SDA, VCC, GND
//    7) test resistor in parallel with voltage sensor (optional, for big capacitance)
//
// © Artem Alekseyenko, 2016

#include <OLED_I2C.h>
#include <SPI.h>
#include <SD.h>
#include "Wire.h"
#define DS3231_I2C_ADDRESS 0x68
File myFile;
OLED  myOLED(SDA, SCL, 8);
extern uint8_t SmallFont[];
extern uint8_t MediumNumbers[];
extern uint8_t BigNumbers[];

const int VoltagePin = A0;
const int CurrentPin = A1;
const int chipSelect = 53;                // cs pin from card reader to this pin on Arduino (Mega 2560 only)

const float Resistor = 216.5;             // External load resistor Ohm = 40.5 or 218.0
                                          // 37400.0;  when no resistor. It's input impedance of voltmeter only

const int FrameLength = 5;                // time frame length for rounding and stat accumulation:
                                          // 2, 5, 10, 15, 20, 30 sec

const float voltage_coefficient = 47.41;  // depends on voltage sensor and arduino board, must be tested and adjusted individually:  40.92
                                          // 47.41 when powered by external power source, 
                                          // 40.92 - default
                                          // 43.75 - when powered by computer

const float minimal_voltage = 0.1;        // from this voltage and above experiment starts, and till this voltage experiment lasts. 1.7

const unsigned long micro_koeff = 1;      // 1 for Farad or 1000 for milliFarad or 1000000 for microFarad.



float VoltageInaccount = 0.0;
float CurrentInaccount = 0.0;
double FaradInaccount = 0.0;
float VoltageValue = 0.0;
long  CurrentValue = 0.0;
float AHforPrint = 0.0;
float Faradadd = 0.0;
float FaradforPrint = 0.0;
float highest_voltage_achieved = 0.0;
boolean recorded = false;
int cap_connected = 0;
boolean working = false;
boolean this_is_the_end = false;
unsigned long FrameCounter = 0;
unsigned long TimeFromStart = 0;
int starting_time = 0;
int loops = 1;
int lastloops = 50;
int frame = 1;
int secs = 0;


// Convert normal decimal numbers to binary coded decimal
byte decToBcd(byte val){  return( (val/10*16) + (val%10) );}
// Convert binary coded decimal to normal decimal numbers
byte bcdToDec(byte val){  return( (val/16*10) + (val%16) );}

void readDS3231time(byte *second,
byte *minute,
byte *hour,
byte *dayOfWeek,
byte *dayOfMonth,
byte *month,
byte *year)
{
  Wire.beginTransmission(DS3231_I2C_ADDRESS);
  Wire.write(0); // set DS3231 register pointer to 00h
  Wire.endTransmission();
  Wire.requestFrom(DS3231_I2C_ADDRESS, 7);
  // request seven bytes of data from DS3231 starting from register 00h
  *second = bcdToDec(Wire.read() & 0x7f);
  *minute = bcdToDec(Wire.read());
  *hour = bcdToDec(Wire.read() & 0x3f);
  *dayOfWeek = bcdToDec(Wire.read());
  *dayOfMonth = bcdToDec(Wire.read());
  *month = bcdToDec(Wire.read());
  *year = bcdToDec(Wire.read());
}

byte readDS3231second()
{
  Wire.beginTransmission(DS3231_I2C_ADDRESS);
  Wire.write(0);
  Wire.endTransmission();
  Wire.requestFrom(DS3231_I2C_ADDRESS, 1);
  byte second = bcdToDec(Wire.read() & 0x7f);
  int secondint = int(second);
  return secondint;
}

void setup()
{
  byte second, minute, hour, dayOfWeek, dayOfMonth, month, year;
  myOLED.begin();
//  myOLED.setFont(SmallFont);
  Wire.begin();
  Serial.begin(9600);
  pinMode(53, OUTPUT);

  readDS3231time(&second, &minute, &hour, &dayOfWeek, &dayOfMonth, &month, &year);

  Serial.print(hour, DEC);
  Serial.print(":");
  if (minute<10) {Serial.print("0");}
  Serial.print(minute, DEC);
  Serial.print(":");
  if (second<10){Serial.print("0");}
  Serial.print(second, DEC);
  Serial.print(" ");
  Serial.print(dayOfMonth, DEC);
  Serial.print("/");
  Serial.print(month, DEC);
  Serial.print("/");
  Serial.println(year, DEC);
  
  Serial.print("Initializing SD card...");
  if (!SD.begin(4)) {
    Serial.println("initialization failed!");
      return;
    }
    Serial.println("initialization done.");
    File myFile = SD.open("discharg.txt", FILE_WRITE);
    if (myFile) {
      myFile.print(hour, DEC);
      myFile.print(":");
      if (minute<10) {myFile.print("0");}
      myFile.print(minute, DEC);
      myFile.print(":");
      if (second<10){myFile.print("0");}
      myFile.print(second, DEC);
      myFile.print(" ");
      myFile.print(dayOfMonth, DEC);
      myFile.print("/");
      myFile.print(month, DEC);
      myFile.print("/");
      myFile.println(year, DEC);

      myFile.print("Resistor: ");
      myFile.print(Resistor);
      myFile.println(" Ohm");
      myFile.println("Time Volts mAmps mAh F_real F_calculated");
      myFile.close();
      Serial.println("done.");
    } else {
      Serial.println("error opening dischag.txt");
    }
  Serial.print("Resistor: ");
  Serial.print(Resistor);
  Serial.println(" Ohm");
  Serial.println("Time Volts mAmps mAh F_real F_calculated");

  // re-open the file for reading:
  myFile = SD.open("discharg.txt");
   if (myFile) {
    //    Serial.println("discharg.txt:");

    // read from the file until there's nothing else in it:
    // while (myFile.available()) {
//      Serial.write(myFile.read());
    // }
    // close the file:
    myFile.close();
  } else {
    // if the file didn't open, print an error:
    Serial.println("error opening discharg.txt");
  }


}

void loop()
{
  if ((working == true) && (this_is_the_end == false)) 
  {
    int currentsecond = readDS3231second();
    if (currentsecond%FrameLength == 1) {recorded = false;};
    if ((currentsecond%FrameLength == 0) && (recorded != true))
    {
      FrameCounter += 1;
      int lengthoftest_hr = FrameCounter * FrameLength / 3600;
      int lengthoftest_min = (FrameCounter - lengthoftest_hr*3600/FrameLength)*FrameLength/60;
      int lengthoftest_sec = (FrameCounter - lengthoftest_hr*3600/FrameLength - lengthoftest_min*60/FrameLength)*FrameLength;
      
      float VforPrint = VoltageInaccount/float(loops);
      float AforPrint = VforPrint*1000/Resistor;
      AHforPrint +=  AforPrint/720.0;
      if (VforPrint != 0) {Faradadd = micro_koeff*FrameLength*AforPrint/(1000*highest_voltage_achieved);};  //   micro*time*Amp/Volt_max
      FaradforPrint += Faradadd;

      float FaradCalculated = abs(micro_koeff*(FrameCounter*FrameLength)/(Resistor*log(VforPrint/highest_voltage_achieved)));   //   /5.0
      FaradInaccount += FaradCalculated;
      myOLED.clrScr();

//    myOLED.setFont(MediumNumbers);
      myOLED.setFont(SmallFont);
    
      myOLED.printNumI(lengthoftest_hr, LEFT, 0);
      myOLED.print(":", 12, 0);
      myOLED.printNumI(lengthoftest_min, 17, 0);
      myOLED.print(":", 30, 0);
      myOLED.printNumI(lengthoftest_sec, 35, 0);
      myOLED.printNumF(highest_voltage_achieved, 2, CENTER, 0);
      myOLED.printNumI(loops, RIGHT, 0);
      myOLED.setFont(MediumNumbers);
      myOLED.printNumF(abs(FaradforPrint), 1, LEFT, 45);
      myOLED.setFont(SmallFont);
      myOLED.print("F ", 38, 45);
      myOLED.setFont(MediumNumbers);
      myOLED.printNumF(FaradCalculated, 1, 70, 45);
//    myOLED.printNumF(abs(AHforPrint), 0, 70, 45);
      myOLED.setFont(SmallFont);
//    myOLED.print("mAh", RIGHT, 45);
      myOLED.print("Fc", RIGHT, 45);
      myOLED.setFont(MediumNumbers);
//    myOLED.printNumF(float(VoltageInaccount/float(circles)), 2, RIGHT, 20);
      myOLED.setFont(SmallFont);
      myOLED.print("V", RIGHT, 25);
      myOLED.setFont(MediumNumbers);
      myOLED.printNumF(VforPrint, 2, 70, 20);
//    myOLED.printNumF(abs(float(CurrentInaccount/float(circles))), 0, LEFT, 40);
//    myOLED.printNumF(abs(float(CurrentInaccount/60.0)), 0, LEFT, 40);
      myOLED.printNumF(AforPrint, 0, LEFT, 20); // abs(
      myOLED.setFont(SmallFont);
      myOLED.print("mA", 38, 25);
      myOLED.setFont(MediumNumbers);
      myOLED.update();

      myFile = SD.open("discharg.txt", FILE_WRITE);
      if (lengthoftest_hr < 10) {myFile.print("0");};
      myFile.print(lengthoftest_hr);
      myFile.print(":");
      if (lengthoftest_min < 10) {myFile.print("0");};
      myFile.print(lengthoftest_min);
      myFile.print(":");
      if (lengthoftest_sec < 10) {myFile.print("0");};
      myFile.print(lengthoftest_sec);
      myFile.print("  ");
      myFile.print(VforPrint);
      myFile.print("  ");
      myFile.print(AforPrint);
      myFile.print("  ");
      myFile.print(abs(AHforPrint));
      myFile.print("  ");
      myFile.print(abs(FaradforPrint));
      myFile.print("  ");
      myFile.println(FaradCalculated);
      myFile.close();

      if (lengthoftest_hr < 10) {Serial.print("0");};
      Serial.print(lengthoftest_hr);
      Serial.print(":");
      if (lengthoftest_min < 10) {Serial.print("0");};
      Serial.print(lengthoftest_min);
      Serial.print(":");
      if (lengthoftest_sec < 10) {Serial.print("0");};
      Serial.print(lengthoftest_sec);
      Serial.print("  ");
      Serial.print(VforPrint);
      Serial.print("  ");
      Serial.print(AforPrint);
      Serial.print("  ");
      Serial.print(AHforPrint);
      Serial.print("  ");
      Serial.print(abs(FaradforPrint));
      Serial.print("  ");
      Serial.println(FaradCalculated);

      myOLED.setFont(SmallFont);
//    myOLED.print(":", LEFT, 9);
//    myOLED.print(":", RIGHT, 9);
//    myOLED.update();
      VoltageInaccount = 0.0;
      CurrentInaccount = 0.0;
      lastloops = loops;
      loops = 0;
      recorded = true;

      if (VforPrint <= minimal_voltage) {
        this_is_the_end = true;
        myFile = SD.open("discharg.txt", FILE_WRITE);
        myFile.print("The end voltage: ");
        myFile.println(VforPrint);
        Serial.print("The end voltage: ");
        Serial.println(VforPrint);
      };
    };
    
//  int shift = 110*loops/lastloops;
//  myOLED.print("o", 7+shift, 9);
    int shift = 120*loops/lastloops;
    myOLED.print("\|", shift, 8);
    myOLED.update();
    
    VoltageValue = analogRead(VoltagePin);
    VoltageValue = float(VoltageValue)/voltage_coefficient;
    VoltageInaccount += VoltageValue;
    loops = loops + 1;
    delay(1);
  } 
  if (working == false){                                     // waiting of cap connection
    myOLED.clrScr();
    myOLED.setFont(SmallFont);
    myOLED.print("Connect a capacitor", CENTER, 30);
    myOLED.update();
    VoltageValue = analogRead(VoltagePin);
    VoltageValue = float(VoltageValue)/voltage_coefficient;
    if (VoltageValue > minimal_voltage)
    {
      cap_connected += 1;
      if (VoltageValue > highest_voltage_achieved) {highest_voltage_achieved = VoltageValue; starting_time = 2 * cap_connected;};
      if (cap_connected > 100) {working = true;};
      if ((cap_connected > 4) && (cap_connected > starting_time)) {working = true;};
      if (working == true)
      {
        myFile = SD.open("discharg.txt", FILE_WRITE);
        myFile.print("The hightst voltage: ");
        myFile.println(highest_voltage_achieved);
        myFile.print("00:00:00  ");
        myFile.print(highest_voltage_achieved);
        float highest_ampers_achieved = highest_voltage_achieved*1000/Resistor;
        myFile.print("  ");
        myFile.print(highest_ampers_achieved);
        myFile.println("  0.0  0.0  0.0");
        myFile.close();
        Serial.print("The hightst voltage: ");
        Serial.println(highest_voltage_achieved);
        Serial.print("00:00:00  ");
        Serial.print(highest_voltage_achieved);
        Serial.print("  ");
        Serial.print(highest_ampers_achieved);
        Serial.println("  0.0  0.0  0.0  0.0");
        VoltageInaccount = highest_voltage_achieved;
        loops = 1;
      }
    }
    delay (10);
  }


  if (this_is_the_end == true)
  {
    delay (1000);
  }
}