Display SSD1306 for ESP32
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#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#define __DEBUG__
//The following constants are used to configure the behaviour of the interface
// MAX_OPTIONS defines the maximum number of options a menu can hold
// MAX_MENUS declares the maximum number of menu screens in the interface
// MAX_GRAPHS is the maximum number of graphs to create
// DISP_WIDTH and DISP_HEIGHT are hardware specific (SSD1306)
// REFRESH: is the time in miliseconds the interface will take in refreshing (this time affects the loop, keep that in mind)
#define MAX_OPTIONS 10 //Maximum number of options for each menu
#define MAX_MENUS 3
#define MAX_GRAPHS 3
#define MAX_MODIFIERS 3
#define DISP_WIDTH 128 // OLED display width
#define DISP_HEIGHT 64 // OLED display height
#define REFRESH 10 //Refresh time in ms
#define ADDRESS 0x3C //I2C address of the display
Adafruit_SSD1306 display(DISP_WIDTH, DISP_HEIGHT, &Wire, -1);
class Option{
private:
int sizex; //Defines the size it will occupy in the x axis (width), this value is gotten from the menu
int sizey; //Defines the height of the option (this value is gotten from the menu it belongs to)
String content; //Text of the option
int pos; //Defines the position it has in the menu
int textSpacing; //According to the height, defines the space for the text, so that it's vertically centered
bool fill = false; //In case an option is not selected this should be false
bool disp = false; //In case an option is not configured, it should be false and, thus hidden
int destinationType; //Defines what the option leads to (another menu, graph, something else)
int destinationIndex; //Defines where the option leads to (index of the destination)
public:
//Option(){}
//Method to configure an option, all attributes are assigned, and disp is true, so the option can be displayed
void configure(String content, int sizex, int sizey, int pos, int destinationType, int destinationIndex){
this->sizex = sizex;
this->sizey = sizey;
this->content = content;
this->pos = pos;
this->destinationType = destinationType;
this->destinationIndex = destinationIndex;
this->disp = true;
this->textSpacing = ((sizey - 7)/2) + 7;
}
int getDestinationType(){
int destinationType = this->destinationType;
return destinationType;
}
int getDestinationIndex(){
int destinationIndex = this->destinationIndex;
return destinationIndex;
}
//This method draws each option
void drawopt(int page, int pos, int optPPage){
if(this->disp){ //Checks if the option was configured and, as a result, is displayable
if(this->pos == pos){ //If the position of the option corresponds to the position passed to the function, then it should be selected
display.fillRect(0, (this->sizey)*(this->pos) + 1 - (page*optPPage*this->sizey), this->sizex, this->sizey, WHITE);
display.setTextColor(SSD1306_BLACK);
display.setCursor(5, (this->sizey)*(this->pos + 1) - (page*optPPage*this->sizey) - this->textSpacing);
display.print(this->content);
display.setTextColor(SSD1306_WHITE);
}
else{ //If the option is not selected, the rectangle containing it shouldn't be filled
display.drawRect(0, (this->sizey)*(this->pos) + 1 - (page*optPPage*this->sizey), this->sizex, this->sizey, WHITE);
display.setCursor(5, (this->sizey)*(this->pos + 1) - (page*optPPage*this->sizey) - this->textSpacing);
display.print(this->content);
}
}
}
};
class Menu{ //ContentType (0)
private:
int sizex; //X size for each option in the menu
int sizey; //Y size of each option in the menu
int options = 0; //This indicates the number of options created
int pos = 0; //This indicates the position of the cursor
int page = 0; //If the menu is too long, this indicates the page that is being displayed
Option opt[MAX_OPTIONS];
int optPPage;
int previousScreen = 0;
int previousContentType = 0;
public:
void configure(int sizex, int sizey){ //This method configures the menu created from Screen
this->sizex = sizex;
this->sizey = sizey;
this->optPPage = DISP_HEIGHT / this->sizey;
}
//The following method is used to created an option for the menu
void createOption(String content, int destinationType, int destinationIndex){
//The option takes the place in the array defined by the options number variable (options), which is later increased.
this->opt[this->options].configure(content, this->sizex, this->sizey, this->options++, destinationType, destinationIndex);
}
int extractDestinationType(){
int destinationType = this->opt[this->pos].getDestinationType();
return destinationType;
}
int extractDestinationIndex(){
int destinationIndex = this->opt[this->pos].getDestinationIndex();
return destinationIndex;
}
//The following method draws the whole menu by drawing every option configured within it
void drawMenu(){
display.clearDisplay();
this->page = pos/this->optPPage; //The current page is obtained by dividing the position by the number of options per page (only integer)
for(int i = 0; i < options; i++){
this->opt[i].drawopt(this->page, this->pos, this->optPPage);
}
display.display();
}
//Methods used by Screen
int extractPos(){ //Gets the current position of the cursor
return(this->pos);
}
int extractOptNumber(){ //Gets the number of options in the menu
return(this->options);
}
void increasePos(){ //Increases the position of the cursor
this->pos++;
}
void decreasePos(){ //Decreases the position of the cursor
this->pos--;
}
//Both of the following methods store the values of the previous screen passed as parameters by Screen
void setPreviousScreen(int prev){
this->previousScreen = prev;
}
void setPreviousContentType(int prev){
this->previousContentType = prev;
}
//Both of the following methods retrieve the values of the screen previous to the menu containing these data.
int getPreviousScreen(){
int prev = this->previousScreen;
return prev;
}
int getPreviousContentType(){
int prev = this->previousContentType;
return prev;
}
};
class Graph{ //ContentType (1)
private:
String title;
char graphType; //'a' Vertical Bar, 'b' Horizontal Bar, 'c' Cartesian Graph
//Assign whatever value in "configure(..." if a parameter is not required for the specified graphType
double value; //For: Vertical Bar Horizontal Bar Cartesian
double xpos; //For: Vertical Bar Horizontal Bar Cartesian
double ypos; //For: Vertical Bar Horizontal Bar Cartesian
double height; //For: Vertical Bar Horizontal Bar Cartesian
double width; //For: Vertical Bar Horizontal Bar Cartesian
double yminimum; //For: Vertical Bar Cartesian
double ymaximum; //For: Vertical Bar Cartesian
double xminimum; //For: Horizontal Bar Cartesian
double xmaximum; //For: Horizontal Bar Cartesian
double yStepSize; //For: Vertical Bar Cartesian
double xStepSize; //For: Horizontal Bar Cartesian
int digit; //For: Vertical Bar Horizontal Bar Cartesian
double x;
double yrange;
double xrange;
double ox;
double oy;
double count;
double graphScale;
bool redraw = true;
int previousScreen = 0;
int previousContentType = 0;
public:
//This method configures the graph created, defines its parameters according the type of graph selected.
void configure(String title, char graphType, double xpos, double ypos, double width, double height,
double yminimum, double ymaximum, double xminimum, double xmaximum, double yStepSize, double xStepSize, int digit){
this->title = title;
this->graphType = graphType;
this->yminimum = yminimum;
this->ymaximum = ymaximum;
this->xminimum = xminimum;
this->count = xminimum;
this->xmaximum = xmaximum;
this->height = height;
this->width = width;
this->yStepSize = yStepSize;
this->xStepSize = xStepSize;
this->digit = digit;
this->xpos = xpos;
this->ypos = ypos;
switch(graphType){
case 'a':
this->yrange = ymaximum - yminimum;
this->graphScale = (yStepSize) * (height / this->yrange) - .001; //Adjusts the scale of the graph, according to the range and the size of the step
break;
case 'b':
this->xrange = xmaximum - xminimum;
this->graphScale = (xStepSize) * (width / this->xrange) - .001; //Adjusts the scale of the graph, according to the range and the size of the step
break;
case 'c':
this->yrange = ymaximum - yminimum;
this->xrange = xmaximum - xminimum;
break;
}
}
void drawGraph(){
double level, data, i;
switch(graphType){
case 'a':
double my;
if (this->redraw) { //Prints the labels
display.clearDisplay();
this->redraw = false;
display.fillRect(0, 0, 127 , 14, SSD1306_WHITE);
display.setTextColor(SSD1306_BLACK, SSD1306_WHITE);
display.setTextSize(1);
display.setCursor(2, 4);
display.println(this->title);
for (i = 0; i <= this->height; i += this->graphScale) {
my = this->ypos - this->height + i;
display.drawFastHLine(this->xpos + this->width + 1, my, 5, SSD1306_WHITE);
// draw lables
display.setTextSize(1);
display.setTextColor(SSD1306_WHITE, SSD1306_BLACK);
display.setCursor(this->xpos + this->width + 12, my - 3 );
data = this->ymaximum - ( i * (this->yStepSize / this->graphScale));
display.print(data, this->digit);
}
}
// compute level of bar graph that is scaled to the height and the hi and low vals
// this is needed to accompdate for +/- range
level = (this->height * (((this->value - this->yminimum) / (this->yrange))));
// draw the bar graph
// write a upper and lower bar to minimize flicker cause by blanking out bar and redraw on update
display.drawRect(this->xpos, this->ypos - this->height, this->width, this->height, SSD1306_WHITE);
display.fillRect(this->xpos, this->ypos - this->height, this->width, this->height - level, SSD1306_BLACK);
display.drawRect(this->xpos, this->ypos - this->height, this->width, this->height, SSD1306_WHITE);
display.fillRect(this->xpos, this->ypos - level, this->width, level, SSD1306_WHITE);
// up until now print sends data to a video buffer NOT the screen
// this call sends the data to the screen
display.display();
break;
case 'b':
if (this->redraw) {
display.clearDisplay();
this->redraw = false;
display.fillRect(0, 0, 127 , 16, SSD1306_WHITE);
display.setTextColor(SSD1306_BLACK, SSD1306_WHITE);
display.setTextSize(1);
display.setCursor(2, 4);
display.println(this->title);
// draw the text
for (i = 0; i <= this->width; i += this->graphScale) {
display.drawFastVLine(i + this->xpos , this->ypos , 5, SSD1306_WHITE);
// draw lables
display.setTextSize(1);
display.setTextColor(SSD1306_WHITE, SSD1306_BLACK);
display.setCursor(i + this->xpos , this->ypos + 10);
// addling a small value to eliminate round off errors
// this val may need to be adjusted
data = ( i * (this->xStepSize / this->graphScale)) + this->xminimum + 0.00001;
display.print(data, this->digit);
}
}
// compute level of bar graph that is scaled to the width and the hi and low vals
// this is needed to accompdate for +/- range capability
// draw the bar graph
// write a upper and lower bar to minimize flicker cause by blanking out bar and redraw on update
level = (this->width * (((this->value - this->xminimum) / (this->xmaximum - this->xminimum))));
display.fillRect(this->xpos + level, this->ypos - this->height, this->width - level, this->height, SSD1306_BLACK);
display.drawRect(this->xpos, this->ypos - this->height, this->width, this->height, SSD1306_WHITE);
display.fillRect(this->xpos, this->ypos - this->height, level, this->height, SSD1306_WHITE);
// up until now print sends data to a video buffer NOT the screen
// this call sends the data to the screen
display.display();
break;
case 'c':
double temp;
if (this->redraw == true) {
this->redraw = false;
display.clearDisplay();
display.fillRect(0, 0, 127 , 16, SSD1306_WHITE);
display.setTextColor(SSD1306_BLACK, SSD1306_WHITE);
display.setTextSize(1);
display.setCursor(2, 4);
display.println(title);
this->ox = (this->count - this->xminimum) * (this->width) / (this->xrange) + this->xpos;
this->oy = (this->value - this->yminimum) * (- this->height) / (this->yrange) + this->ypos;
// draw y scale
display.setTextSize(1);
display.setTextColor(SSD1306_WHITE, SSD1306_BLACK);
for ( i = this->yminimum; i <= this->ymaximum; i += this->yStepSize) {
// compute the transform
// note my transform funcition is the same as the map function, except the map uses long and we need doubles
temp = (i - this->yminimum) * (- this->height) / (this->ymaximum - this->yminimum) + this->ypos;
if (i == 0) {
display.drawFastHLine(this->xpos - 3, temp, this->width + 3, SSD1306_WHITE);
}
else {
display.drawFastHLine(this->xpos - 3, temp, 3, SSD1306_WHITE);
}
display.setCursor(this->xpos - 27, temp - 3);
display.println(i, this->digit);
}
// draw x scale
for (i = this->xminimum; i <= this->xmaximum; i += this->xStepSize) {
// compute the transform
display.setTextSize(1);
display.setTextColor(SSD1306_WHITE, SSD1306_BLACK);
temp = (i - this->xminimum) * (this->width) / (this->xrange) + this->xpos;
if (i == 0) {
display.drawFastVLine(temp, this->ypos - this->height, this->height + 3, SSD1306_WHITE);
}
else {
display.drawFastVLine(temp, this->ypos, 3, SSD1306_WHITE);
}
display.setCursor(temp, this->ypos + 6);
display.println(i, this->digit);
}
}
// graph drawn now plot the data
// the entire plotting code are these few lines...
this->x = (this->count - this->xminimum) * (this->width) / (this->xrange) + this->xpos;
this->value = (this->value - this->yminimum) * (- this->height) / (this->yrange) + this->ypos;
display.drawLine(this->ox, this->oy, this->x, this->value, SSD1306_WHITE);
display.drawLine(this->ox, this->oy - 1, this->x, this->value - 1, SSD1306_WHITE);
this->ox = this->x;
this->oy = this->value;
// up until now print sends data to a video buffer NOT the screen
// this call sends the data to the screen
display.display();
this->count += 1;
if(this->ox >= (this->xpos + this->width)){
this->redraw = true;
this->count = xminimum;
}
}
}
void redrawFlag(){ // Activates the redraw bool to get the graph printed correctly
this->redraw = true;
}
void setPreviousScreen(int prev){
this->previousScreen = prev;
}
void setPreviousContentType(int prev){
this->previousContentType = prev;
}
int getPreviousScreen(){
int prev = this->previousScreen;
return prev;
}
int getPreviousContentType(){
int prev = this->previousContentType;
return prev;
}
void assignValue(double value){
this->value = value;
}
void reset(){
this->x = 0;
}
};
class Modifier{ //ContentType (2)
private:
String title;
int *value;
int max;
int min;
int step;
int previousScreen = 0;
int previousContentType = 0;
public:
void configure(String title, int *value, int max, int min, int step){
this->title = title;
this->value = value;
this->max = max;
this->min = min;
this->step = step;
}
void drawModifier(){
display.clearDisplay();
display.fillRect(0, 0, 127 , 16, SSD1306_WHITE);
display.setTextColor(SSD1306_BLACK, SSD1306_WHITE);
display.setTextSize(1);
display.setCursor(2, 4);
display.println(this->title);
display.setTextColor(SSD1306_WHITE);
display.setTextSize(3);
display.setCursor(2, ((DISP_HEIGHT - 16 - 15)/2) + 16);
display.println(*this->value);
display.display();
display.setTextSize(1);
}
void increaseValue(){
if((*this->value + this->step) <= this->max){
*this->value += this->step;
}
}
void decreaseValue(){
if((*this->value - this->step) >= this->min){
*this->value -= this->step;
}
}
void setPreviousScreen(int prev){
this->previousScreen = prev;
}
void setPreviousContentType(int prev){
this->previousContentType = prev;
}
int getPreviousScreen(){
int prev = this->previousScreen;
return prev;
}
int getPreviousContentType(){
int prev = this->previousContentType;
return prev;
}
};
class Screen{
private:
Menu menu[MAX_MENUS]; //Array of menus to use
Graph graph[MAX_GRAPHS]; //Array of graphs to use
Modifier modifier[MAX_MODIFIERS]; //Array of modifiers to use
int counterM = 0; //Number of menus created
int counterG = 0; //Number of graphs created
int counterMod = 0;
bool redraw = true; //Redraw interface for when there is a change of screen
int currentScreen = 0;
int contentType = 0;
public:
void configure(bool fullsetting){ //This method allows the configuration of the display when the parameter is true. Otherwise only prints a greeting message.
if(fullsetting){
//Adafruit_SSD1306 display(DISP_WIDTH, DISP_HEIGHT, &Wire, -1);
Serial.begin(115200);
if (!display.begin(SSD1306_SWITCHCAPVCC, ADDRESS)) {
#ifdef __DEBUG__
Serial.println("Display not found!");
#endif
while (true);
}
}
display.clearDisplay();
// Text size
display.setTextSize(2);
// Text color
display.setTextColor(SSD1306_WHITE);
// Text position
display.setCursor(25, 20);
display.println("Welcome");
display.setTextSize(1);
display.display();
delay(5000);
}
void createMenu(int sizex, int sizey){ //This method is used for the creation of a menu
this->menu[counterM].configure(sizex, sizey);
this->counterM++;
}
void createOption(int menuIndex, String content, int destinationType, int destinationIndex){ //this method should be used for creating an option in a menu
this->menu[menuIndex].createOption(content, destinationType, destinationIndex);
}
void createVGraph(String title, double xpos, double ypos, double width, double height,
double yminimum, double ymaximum, double yStepSize, int digit){ //this method calls the configure() of graph for a vertical graph
this->graph[counterG].configure(title, 'a', xpos, ypos, width, height, yminimum, ymaximum, 0, 0, yStepSize, 0, digit);
this->counterG++;
}
void createHGraph(String title, double xpos, double ypos, double width, double height,
double xminimum, double xmaximum, double xStepSize, int digit){ //this method calls the configure() of graph for a horizontal graph
this->graph[counterG].configure(title, 'b', xpos, ypos, width, height, 0, 0, xminimum, xmaximum, 0, xStepSize, digit);
counterG++;
}
void createCGraph(String title, double xpos, double ypos, double width, double height,
double yminimum, double ymaximum, double xminimum, double xmaximum, double yStepSize, double xStepSize, int digit){ //this method calls the configure() of graph for a cartesian chart
this->graph[counterG].configure(title, 'c', xpos, ypos, width, height, yminimum, ymaximum, xminimum, xmaximum, yStepSize, xStepSize, digit);
counterG++;
}
void createModifier(String title, int *value, int max, int min, int step){ //This method is used for the creation of a menu
this->modifier[counterMod].configure(title, value, max, min, step);
this->counterMod++;
}
/*
void redrawFlag(){
this->redraw = true;
}
*/
//The following method is used for assingning a value to a graph
//This can be avoided using pointers to the variable to plot in the graph
void graphAssignValue(int graphIndex, double value){
this->graph[graphIndex].assignValue(value);
if(this->currentScreen == graphIndex && this->contentType == 1)
this->redraw = true;
}
//This method controls the whole interface, it needs to be called within a loop
void control(){
if (redraw){
if (contentType == 0){
menu[currentScreen].drawMenu();
}
else if (contentType == 1){
graph[currentScreen].drawGraph();
}
else if (contentType == 2){
modifier[currentScreen].drawModifier();
}
this->redraw = false;
}
}
//The following two methods allow the change in position of the cursor
void increasePos(){
if(this->menu[this->currentScreen].extractPos() < this->menu[this->currentScreen].extractOptNumber() - 1)
this->menu[this->currentScreen].increasePos();
}
void decreasePos(){
if(this->menu[this->currentScreen].extractPos() > 0)
this->menu[this->currentScreen].decreasePos();
}
//This method lets the user go into another screen by selecting an option
void goTo(){
if(this->contentType == 0){
int newScreen = this->menu[this->currentScreen].extractDestinationIndex();
int newContentType = this->menu[this->currentScreen].extractDestinationType();
if (newContentType == 0){
this->menu[newScreen].setPreviousScreen(this->currentScreen);
this->menu[newScreen].setPreviousContentType(this->contentType);
}
else if(newContentType == 1){
this->graph[newScreen].setPreviousScreen(this->currentScreen);
this->graph[newScreen].setPreviousContentType(this->contentType);
this->graph[newScreen].reset();
this->graph[newScreen].redrawFlag();
}
else if(newContentType == 2){
this->modifier[newScreen].setPreviousScreen(this->currentScreen);
this->modifier[newScreen].setPreviousContentType(this->contentType);
}
this->contentType = newContentType;
this->currentScreen = newScreen;
this->redraw = true;
}
}
void goBack(){
if(contentType == 0){
//Gets indexes from previous screen saved in actual screen if it is a menu, and sets them as the current indexes
this->currentScreen = this->menu[this->currentScreen].getPreviousScreen();
this->contentType = this->menu[this->currentScreen].getPreviousContentType();
}
else if(contentType == 1){
//Gets indexes from previous screen saved in actual screen if it is a graph, and sets them as the current indexes
this->currentScreen = this->graph[this->currentScreen].getPreviousScreen();
this->contentType = this->graph[this->currentScreen].getPreviousContentType();
}
else if(contentType == 2){
this->currentScreen = this->modifier[this->currentScreen].getPreviousScreen();
this->contentType = this->modifier[this->currentScreen].getPreviousContentType();
}
this->redraw = true;
}
//These methods control the plus and minus button actions
void plusAction(){
if(contentType == 0){
increasePos();
}
else if(contentType == 2){
this->modifier[currentScreen].increaseValue();
}
this->redraw = true;
}
void minusAction(){
if(contentType == 0){
decreasePos();
}
else if(contentType == 2){
this->modifier[currentScreen].decreaseValue();
}
this->redraw = true;
}
};
class Keyboard{
private:
byte goTo;
byte goBack;
byte plus;
byte minus;
byte debounceTime;
Screen *screen;
public:
//Keyboard constructor
Keyboard(byte goTo, byte goBack, byte plus, byte minus, byte debounceTime, Screen * screen){
this->goTo = goTo;
this->goBack = goBack;
this->plus = plus;
this->minus = minus;
this->debounceTime = debounceTime;
this->screen = screen;
pinMode(goTo, INPUT_PULLUP);
pinMode(goBack, INPUT_PULLUP);
pinMode(plus, INPUT_PULLUP);
pinMode(minus, INPUT_PULLUP);
}
//Debouncing functions
void checkGoTo(){
static char cont;
if(digitalRead(this->goTo) == LOW)
cont++;
else
cont = 0;
if(cont == debounceTime/REFRESH){
this->screen->goTo();
}
}
void checkGoBack(){
static char cont;
if(digitalRead(this->goBack) == LOW){
cont++;
}
else
cont = 0;
if(cont == debounceTime/REFRESH){
this->screen->goBack();
}
}
void checkPlus(){
static char cont;
if(digitalRead(this->plus) == LOW)
cont++;
else
cont = 0;
if(cont == debounceTime/REFRESH){
this->screen->plusAction();
}
}
void checkMinus(){
static char cont;
if(digitalRead(this->minus) == LOW)
cont++;
else
cont = 0;
if(cont == debounceTime/REFRESH){
this->screen->minusAction();
}
}
// All buttons are checked with this method
void control(){
this->checkGoTo();
this->checkGoBack();
this->checkPlus();
this->checkMinus();
}
};
int i = 0;
int multiplier = 1;
Screen screen;
Keyboard keyboard(13, 12, 14, 27, 30, &screen);
void setup(){
screen.configure(true);
screen.createMenu(128, 13); //Menu 0
screen.createMenu(128, 13); //Menu 1
/*String title, char graphType, double xpos, double ypos, double width, double height,
double yminimum, double ymaximum, double xminimum, double xmaximum, double yStepSize, double xStepSize, double digit*/
screen.createVGraph("Grafica 1", 25, 60, 40, 40, 0, 100, 10, 0); //Graph 0
screen.createHGraph("Grafica 2", 10, 40, 100, 20, 0, 100, 10, 0); //Graph 1
screen.createCGraph("Grafica 3", 30, 50, 75, 30, 0, 100, 0, 1000, 25, 250, 0); //Graph 2
screen.createModifier("Modify variable", &multiplier, 5, 1, 1);
screen.createOption(0, "Vertical graph", 1, 0);
//Creates the first option in Menu 0, directing to a graph (contentType = 1 (Graph)), 0 (Graph 0)
screen.createOption(0, "Horizontal graph", 1, 1);
screen.createOption(0, "Cartesian graph", 1, 2);
screen.createOption(0, "Extra option", 0, 1);
screen.createOption(1, "Test", 1, 3);
screen.createOption(1, "Working?", 2, 2);
screen.createOption(1, "Modify variable", 2, 0);
// screen.increasePos();
// screen.increasePos();
// screen.goTo();
// screen.graphAssignValue(2, 50);
// screen.goBack();
// screen.increasePos();
// screen.goTo();
// screen.goBack();
// screen.decreasePos();
}
void loop(){
screen.control(); //Controls the screen and redraws if needed
keyboard.control();
if(i <= 100){
screen.graphAssignValue(1, i); //Assigning a demo value to Graph 1
screen.graphAssignValue(2, i); //Assigning a demo value to Graph 2
i += multiplier;
}
else
i = 0;
delay(REFRESH); //Refresh time (approx)
}