How to save a constant updating value

Projects Programming
18

Is this better?

#include <serLCD.h>
#include <SoftwareSerial.h>
#include <LiquidCrystal.h>
#include <math.h>

int oldval=0; //sec value for the button
int state1=0;  //state the button is in
int val = 0; //first value for the button
const int button = 7; //pin for the push button (for testing)

// these constants won't change:
const int xPin = 2;     // X output of the accelerometer
const int yPin = 3;     // Y output of the accelerometer
//Button Left And Right pins (for use later)
int right = 4;
int left = 5;
// Set pin to the LCD's rxPin
int pin = 1;
serLCD lcd(pin);

int Xraw, Yraw;
double xGForce, yGForce, Xangle, Yangle;
double saveY, saveX, state;

void setup() 
{
  // initialize serial communications:
  Serial.begin(9600);
  // initialize the pins connected to the accelerometer
  // as inputs:
  pinMode(xPin, INPUT);
  pinMode(yPin, INPUT);

  Serial.write(0xFE);   //command flag
  Serial.write(0x01);   //clear command.
  delay(10);

  Serial.print("Lets Begin");
  delay(1000);
}

void loop()
{
  //   lcd.clear();
  Serial.write(0xFE);   //command flag
  Serial.write(0x01);   //clear command.
  delay(10);
  // variables to read the pulse widths:
  int pulseX, pulseY;
  // variables to contain the resulting accelerations
  int accelerationX, accelerationY;

  // read pulse from x- and y-axes:
  pulseX = pulseIn(xPin,HIGH);  
  pulseY = pulseIn(yPin,HIGH);

  Xraw = pulseIn (xPin, HIGH);
  Xraw = pulseIn (xPin, HIGH);
  Yraw = pulseIn (yPin, HIGH);
  Yraw = pulseIn (yPin, HIGH);

  // Calculate G-force in Milli-g's.

  xGForce = (( Xraw / 10 ) - 500) * 8;
  yGForce = (( Yraw / 10 ) - 500) * 8;

  // Calculate angle (radians) for both -x and -y axis.

  Xangle = asin ( xGForce / 1000.0 );
  Yangle = asin ( yGForce / 1000.0 );

  // Convert radians to degrees.

  Xangle = Xangle * (360 / (2*M_PI));
  Yangle = Yangle * (360 / (2*M_PI));

  //save angle when button is pushed, then compare to live reading send a zero once live reading
  //is below saved angle

  Serial.print("Y Angle: ");
  Serial.print(Yangle);
  val= digitalRead(button); //Read input
  if ((val==HIGH) && (oldval==LOW))
  {
    test(saveY);
    Serial.print(saveY);
  } 
  else if (Yangle <= -10) 
  {
    Serial.write(0xFE);   //command flag
    Serial.write(192);    //position
    Serial.print(saveY);
    delay(150);
  } 
  else 
  {
    Serial.write(0xFE);   //command flag
    Serial.write(192);    //position
    Serial.print(saveY);
    delay(150);
  }
}

int test(int saveY) 
{
  Serial.write(0xFE);   //command flag
  Serial.write(192);    //position
  saveY=Yangle;
  Serial.print(saveY);
  delay(150);
  return saveY;
}

EDIT: I was at first using the sparkfun MPU 6050 https://www.sparkfun.com/products/11028? but that quickly proved to be much bigger of a beast then i thought.

So i decided to use the accelerometer. They say its accurate up to 45 degrees and its easy to code. Needing this for a class i figured i could refine it as i start using it. But having it flat moving it across the table it does give me wild readings with the accel. Thnk you for pointing that out. I might be able to implement the accel into a new version where i would use the accel to compare speeds for the auto shut off.

What kind of easy programable chip do you guys recommend that i can use for this project? Or has anyone used the MPU 6050 with their arduino project? Also would still be interested in fixing my problem i have so i wont have it later in the future.