Project showcase

Arduino Addons: Battery Level Indicator © GPL3+

A realtime battery indicator for your project without extra components or using any analog I/Os.

  • 14,443 views
  • 18 comments
  • 54 respects

Components and supplies

Apps and online services

About this project

Several times I've wished I had a battery indicator in my battery-powered projects, but it uses so many custom characters in the LCD and sacrifice analog input for voltage indication and components and connections. So we decided to do it the smart way and push the Arduino to its limits "as we always do" and get the maximum out of it.

In this project we use only one custom character from the LCD. So you still have seven free custom characters to use in your project. We also used the trick of reff voltage to get the input voltage from the Arduino without using any analog inputs or components, looks like the complete package.

All you have to is add the function that displays the indicator in the loop function and add the place where you wanted to display it and you are ready.

Enjoy

Download Code

Code

Battery indicatorC/C++
#include <LiquidCrystal.h>
// select the pins used on the LCD panel
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);
void setup() {
  // Initialize LCD
    lcd.begin(16 , 2);
}

void loop() {
  // load battery icon on position 15,0
  batterylevel(15,0);
  
}
//draw battery level in position x,y
void batterylevel(int xpos,int ypos)
{
  //read the voltage and convert it to volt
  double curvolt = double( readVcc() ) / 1000;
  // check if voltge is bigger than 4.2 volt so this is a power source
  if(curvolt > 4.2)
  {
    byte batlevel[8] = {
    B01110,
    B11111,
    B10101,
    B10001,
    B11011,
    B11011,
    B11111,
    B11111,
    };
    lcd.createChar(0 , batlevel);
    lcd.setCursor(xpos,ypos);
    lcd.write(byte(0));
  }
  if(curvolt <= 4.2 && curvolt > 4.0)
  {
    byte batlevel[8] = {
    B01110,
    B11111,
    B11111,
    B11111,
    B11111,
    B11111,
    B11111,
    B11111,
    };
    lcd.createChar(0 , batlevel);
    lcd.setCursor(xpos,ypos);
    lcd.write(byte(0));
  }
  if(curvolt <= 4.0 && curvolt > 3.8)
  {
    byte batlevel[8] = {
    B01110,
    B10001,
    B11111,
    B11111,
    B11111,
    B11111,
    B11111,
    B11111,
    };
    lcd.createChar(0 , batlevel);
    lcd.setCursor(xpos,ypos);
    lcd.write(byte(0));
  }
  if(curvolt <= 3.8 && curvolt > 3.6)
  {
    byte batlevel[8] = {
    B01110,
    B10001,
    B10001,
    B11111,
    B11111,
    B11111,
    B11111,
    B11111,
    };
    lcd.createChar(0 , batlevel);
    lcd.setCursor(xpos,ypos);
    lcd.write(byte(0));
  }
  if(curvolt <= 3.6 && curvolt > 3.4)
  {
    byte batlevel[8] = {
    B01110,
    B10001,
    B10001,
    B10001,
    B11111,
    B11111,
    B11111,
    B11111,
    };
    lcd.createChar(0 , batlevel);
    lcd.setCursor(xpos,ypos);
    lcd.write(byte(0));
  }
  if(curvolt <= 3.4 && curvolt > 3.2)
  {
    byte batlevel[8] = {
    B01110,
    B10001,
    B10001,
    B10001,
    B10001,
    B11111,
    B11111,
    B11111,
    };
    lcd.createChar(0 , batlevel);
    lcd.setCursor(xpos,ypos);
    lcd.write(byte(0));
  }
  if(curvolt <= 3.2 && curvolt > 3.0)
  {
    byte batlevel[8] = {
    B01110,
    B10001,
    B10001,
    B10001,
    B10001,
    B10001,
    B11111,
    B11111,
    };
    lcd.createChar(0 , batlevel);
    lcd.setCursor(xpos,ypos);
    lcd.write(byte(0));
  }
  if(curvolt < 3.0)
  {
    byte batlevel[8] = {
    B01110,
    B10001,
    B10001,
    B10001,
    B10001,
    B10001,
    B10001,
    B11111,
    };
    lcd.createChar(0 , batlevel);
    lcd.setCursor(xpos,ypos);
    lcd.write(byte(0));
  }
}
//read internal voltage
long readVcc() {
  long result;
  // Read 1.1V reference against AVcc
  ADMUX = _BV(REFS0) | _BV(MUX3) | _BV(MUX2) | _BV(MUX1);
  delay(2); // Wait for Vref to settle
  ADCSRA |= _BV(ADSC); // Convert
  while (bit_is_set(ADCSRA, ADSC));
  result = ADCL;
  result |= ADCH << 8;
  result = 1126400L / result; // Back-calculate AVcc in mV
  return result;
}

Comments

Similar projects you might like

uBUG

Project showcase by JHG

  • 1,873 views
  • 4 comments
  • 7 respects

Play Polyphonic Tones!

by nathan_ramanathan

  • 3,670 views
  • 5 comments
  • 10 respects

Arduino Tutorial: JARVIS v1 | How to make a Home Automation

Project tutorial by rahulkhanna

  • 6,226 views
  • 10 comments
  • 50 respects

Electric Kiln Controller

Project showcase by MrRoboto19

  • 826 views
  • 0 comments
  • 8 respects

Retro 1980s LED Clock/Count Up Timer

Project in progress by randtekk

  • 1,410 views
  • 4 comments
  • 10 respects

Pedometer (Arduino 101)

Project tutorial by Frank Williams

  • 242 views
  • 0 comments
  • 2 respects
Add projectSign up / Login