Arduino Calculator Source

8/10/2019 Arduino Calculator Source

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/*

Arduino Calculator

UWB Spring 2012 CSS427 Final Project

----

Jason Woodring

Alexander Johnson

Oonagh Geldenhuys

Joshua Smith

*/

/* -------------------------------- LCD SETUP ----------------------------

/*

Library originally added 18 Apr 2008

by David A. Mellis

library modified 5 Jul 2009

by Limor Fried (http://www.ladyada.net)

example added 9 Jul 2009

by Tom Igoe

modified 22 Nov 2010

by Tom Igoe

*/

#include

/*

The circuit:

* LCD RS pin to digital pin 12

* LCD Enable pin to digital pin 11

* LCD D4 pin to digital pin 5




* LCD R/W pin to ground

* 10K resistor:

* ends to +5V and ground

* wiper to LCD VO pin (pin 3)

*/

// initialize the library with the numbers of the interface pins

LiquidCrystallcd(12, 11, 5, 4, 3, 2);

/* -------------------------------- KEYPAD SETUP -------------------------

/*

Keypad Library for Arduino

Author: Mark Stanley, Alexander Brevig

Contact: [email protected], [email protected]

*/


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#include

#include

// set up the Keypad

constbyteROWS = 5;// Four rows

constbyteCOLS = 4;// Four columns

// Define the Keymap

charkeys[ROWS][COLS] =

{

{'+','7','8','9'}, // row 1

{'-','4','5','6'}, // row 2

{'*','1','2','3'}, // row 3

{'/','0','.','_'}, // row 4

{'C','?','?','='}, // row 5

};

// Connect keypad ROW1, ROW2, ROW3 and ROW4 to these Arduino pins.

byterowPins[ROWS] = {47, 45, 43, 41, 39};

// Connect keypad COL1, COL2, COL3, COL4 to these Arduino pins.

bytecolPins[COLS] = {24, 26, 28, 30};

// Create the Keypad

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

/* -------------------------------- FUNCTIONS ----------------------------

voidsetup()

{

Serial.begin(9600);

lcd.clear();

// set up the LCD's number of columns and rows:

lcd.begin(16, 2);

}

// performs operation on prevNum and nextNum as indicated by calcState

voidperformCalc(short calcState,float &prevNum,float &nextNum,shortdec

{

switch(calcState)

{

case 0:// default

{

prevNum = nextNum;

lcd.clear();


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displayHelper(calcState, nextNum, decPlacement);

//nextNum = 0.0;

break;

}

case 1:// addition

{

prevNum += nextNum;

nextNum = prevNum;

lcd.clear();

lcd.print("Result"); //prints result on the top row

lcd.setCursor(0,1); //sets the cursor to the start of the lower r

displayHelper(calcState, nextNum, decPlacement);//prints results

break; //others are similar so no comments are ad

}

case 2:// subtraction

{

prevNum -= nextNum;

nextNum = prevNum;

lcd.clear();

lcd.print("Result");

lcd.setCursor(0,1);


break;

}

case 3:// multiplication

{

prevNum *= nextNum;

nextNum = prevNum;

lcd.clear();


lcd.setCursor(0,1);


break;

}

case 4:// division

{

lcd.clear();


lcd.setCursor(0,1);

if(nextNum == 0.0) //checks for division by zero and displays erro

{

lcd.print("Zero Division!");

break;

}


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else

{

prevNum /= nextNum;

nextNum = prevNum;

displayHelper(calcState,nextNum, decPlacement);

break;

}

}

}

newEntry =true;

}

int i;//so it isnt created each time it is called

float val;//same as above

voiddisplayHelper(short calcState,floatprintNumber ,shortdecPlacement

{

//value is at the point that the screen acts up so it is the max value t

if( printNumber > 99999999.0)

{

lcd.print("Outside of Range");

return;

}

/*

// No calculations so it only used the last decimal place to print the nu

if(calcState == 0)

{

if(decPlacement > 4)

lcd.print(printNumber, 4);

else

lcd.print(printNumber, decPlacement);

return;

}*/

/*

//A calculation was made so it needs to find the smallest decimal number

else{

// the val is manipulated to find the smallest dec place needed to prin

val = printNumber;

for (i = 0; i < 5; i++)

{

//returns the % of the val (have to use this since it is a float)

val = fmod(val, 1.0);

if(val == 0)//the last dec place has been reached

{

lcd.print(printNumber, i);//print to that point


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return;

}

val *= 10.0;//moves the dec place over one

}

*/

lcd.print(printNumber, 4); //prints the default max range

// }

}

/* -------------------------------- ARDUINO MAIN PROGRAM ENTRY POINT ------

voidloop()

{

// variable setup

char key ='?'; // the current key being pressed

float prevNum = 0.0;// last entered number or result of last calculat

float nextNum = 0.0;// number which is currently being keyed in by us

float offset = 1.0;// Each number will be multiplied by it to eithe

shortcalcState = 0;// indicates calculation to perform when equals key

bool decOffset =false; // Indicates if the offset needs to shift right

floatdecPlace = 1.0;//the offset that is used for dec placement

shortdecCounter = 0;//counter so that it can only go to 4 dec places

bool newEntry =true; // Detects if newly entered number will follow old

/*

0 = nextNum gets stored in prevNum (default)

1 = nextNum gets added to prevNum and the result is stored in prevNum

2 = nextNum gets subtracted from prevNum and the result is stored in

3 = nextNum gets multiplied by prevNum and the result is stored in pr

4 = nextNum gets divided from prevNum and the result is stored in pre

*/

lcd.print("Calculator Ready");

// main loop

while(true)

{

if(decOffset){ //if the decimal point has been clicked it loops throug

if(decCounter == 1)

decPlace = 0.1;

elseif(decCounter == 2)

decPlace = 0.01;


decPlace = 0.001;


decPlace = 0.0001;

}


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key = keypad.getKey();

switch(key)

{

case'0': // zero key has been pressed

{

if(newEntry)

{

nextNum = 0;

newEntry =false;

}

if(!decOffset)

nextNum *= 10.0;

if(decCounter


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if(!decOffset)

nextNum *= 10.0;

if(decCounter


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}

case'5': // five key has been pressed

{

if(newEntry)

{

nextNum = 0;

newEntry =false;

}

if(!decOffset)

nextNum *= 10.0;

if(decCounter


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if(decCounter


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{

if(nextNum == 0.0)

{

// current operand has already been cleared, so clear previo

prevNum = 0.0;

calcState = 0;

offset = 1.0;

}

else

{

// clear the current operand

nextNum = 0.0;

offset = 1.0;

}

decOffset =false;

decPlace = 1.0;

decCounter = 0;

// update display to reflect cleared state

lcd.clear();

lcd.print("Calculator Ready");

break;

}

case'+': // addition key has been pressed

{

performCalc(calcState, prevNum, nextNum, decCounter, newEntry)

calcState = 1;

decOffset =false;

decPlace = 1.0;

nextNum = 0.0;

offset = 1.0;

decCounter = 0;

break;

}

case'-': // subtraction key has been pressed

{


calcState = 2;

decOffset =false;

decPlace = 1.0;

nextNum = 0.0;

offset = 1.0;

decCounter = 0;

break;

}

case'*': // multiplication key has been pressed


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{


calcState = 3;

decOffset =false;

decPlace = 1.0;

nextNum = 0.0;

offset = 1.0;

decCounter = 0;

break;

}

case'/': // division key has been pressed

{


calcState = 4;

decOffset =false;

decPlace = 1.0;

nextNum = 0.0;

offset = 1.0;

decCounter = 0;

break;

}

case'=': // equals key has been pressed

{


calcState = 0;

decOffset =false;

decPlace = 1.0;

offset = 1.0;

decCounter = 0;

break;

}

case'.': // decimal key has been pressed

{

if(newEntry)

{

nextNum = 0;

newEntry =false;

}

if(!decOffset)

{

decCounter = 1;

decPlace = 1.0;

decOffset =true; //sets the decimal offset flag to true, it

// turned off in the middle of a number

}

break;


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}

case'_': // negative key has been pressed

{

offset *= -1.0;//changes the offset so the neg key can be presse

lcd.clear();

if(nextNum == 0.0) //if there is no number to display then just

lcd.print("-");

else{

if(nextNum < 0)

nextNum *= -1;

else

nextNum *= offset;//sets the current number to the neg offset

displayHelper(calcState, nextNum, decCounter);

}

break;

}

}

}

}

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