Diff: main.cpp

Revision:

2:0dfa60f22f07

Parent:

1:32b9ad362749

Child:

3:ee005c9f0348

--- a/main.cpp	Wed May 04 14:18:38 2016 +0000
+++ b/main.cpp	Wed May 04 22:45:02 2016 +0000
@@ -70,32 +70,31 @@
 }
 void init_K64F()
 {
-    // on-board LEDs are active-low, so set pin high to turn them off.
-    r_led = 1;
+    r_led = 1;// on-board LEDs are active-low, so set pin high to turn them off.
     g_led = 1;
     b_led = 1;
-    button2.fall(&mode); //under this condition call function
+    button2.fall(&mode); //under this condition call function where mode is a function that sets flag
     button2.mode(PullUp); //enable internal pull up resistor
-    button1.fall(&units);
-    button1.mode(PullUp);
+    button1.fall(&units);  //under this condition call function where mode is a function that sets flag
+    button1.mode(PullUp); //enable internal pull up resistor
 
 }
 void units()
 {
-    g_button1_flag =!g_button1_flag ;   // set flag in ISR
+    g_button1_flag =!g_button1_flag ;   // set button 1 flag in ISR
 }
 void mode()
 {
-    g_button2_flag =!g_button2_flag ;
+    g_button2_flag =!g_button2_flag ;    //set button 2 flag in ISR
 }
 void timeout_isr()
 {
 }
 void ticker_isr()
 {
-    g_ticker_flag = 1;
+    g_ticker_flag = 1;   // set ticker flag in ISR
 }
-void initialScreen()
+void initialScreen() // initial screen printed
 {
     lcd.printString("DISTANCE",18,0);
     lcd.printString("SENSOR",22,1);
@@ -107,51 +106,51 @@
 {
     //graphArray[82]; //initialize graph array, 2 pixels used for y axis so not 84
     for (int i=0; i<83; i++) { // before entering the grpah mode with the button, it is alreadt plotting points but they cannot be seen as they are above max range of 200
-        graphArray[i] = 201; // has to be more thn 200
+        graphArray[i] = 201; // has to be more thn 200 so points are only plotted from the point when user presses button
     }
     lcd.clear();
 }
-void get_averageDistance()
+void get_averageDistance() // to minimize error, 5 readings are taken at regular intervals and averaged out 
 {
     for ( int i=0 ; i<5; i++) {
-        int distance = sensor.getDistanceCm();
-        if (distance < 400) { //better averages random annomous values not even considere
+        int distance = sensor.getDistanceCm(); // obtaining sensor distance reading
+        if (distance < 400) { //better averages random annomous values not even considered
             averageDistance += distance; //assignment by sum
         } else {
             i--;  //if distance > 400 do not take that reading into account go again
         }
     }
-    averageDistance = averageDistance/5;
+    averageDistance = averageDistance/5; //sum of 5 readings divided by 5 to get average
    lcd.clear();
 }
 
-void redLedIndicator()
+void redLedIndicator() // this function evaluates the average distance reading, displays it and controls the auditory + visual alerts 
 {
     if (averageDistance<=30) {
-        myled = 1;
-        lcd.clear();
-        lcd.printString(" ***COLLISION ",2,1);
+        myled = 1;  // warning led comes on
+        lcd.clear(); // clear previous distance values displayed
+        lcd.printString(" ***COLLISION ",2,1); //warning text
         lcd.printString(" WARNING***   ",8,3);
         lcd.refresh();
-        buzzer = delay; // duty cycle
-        buzzer.period(0.001); //set pwm to my freq
+        buzzer = delay; // duty cycle, volume of buzzer controlled with pot
+        buzzer.period(0.001); //highest frequency pitch when warning message comes on
     } else {
-        r_led = 1;
-        g_led = 1;
-        b_led = 1;
+      //  r_led = 1;
+      //  g_led = 1;
+      //  b_led = 1;
         myled = 0;
     }
-    if (averageDistance >30) {
+    if (averageDistance >30) {  // above critical distance
         lcd.clear();
-        char str[10];
-        if (g_button1_flag == 0) {
+        char str[10]; //keep the string as character array in local stack so can be manipulated
+        if (g_button1_flag == 0) {  //button 1 flag is set 0 by default so distance displayed in units of cm
 
-            sprintf(str,"%.2f",averageDistance);
-            lcd.printString("cm",62,4);
+            sprintf(str,"%.2f",averageDistance); // printing first 2 digits of average distance as float
+            lcd.printString("cm",62,4); // printing units 
 
-        } else  if (g_button1_flag == 1) {
-            sprintf(str,"%.2f",averageDistance*0.393701);
-            lcd.printString("in",60,4);
+        } else  if (g_button1_flag == 1) {  //button 1 pressed, flag set 1 
+            sprintf(str,"%.2f",averageDistance*0.393701); //converting from cm to inches
+            lcd.printString("in",60,4); // printing the units
 
         }
         lcd.printString("                                  ",0,3);
@@ -159,30 +158,30 @@
         lcd.refresh();
     }
 }
-void drawDistanceBars()
+void drawDistanceBars() // function draws bars so as to indicate the approximate distance to nearest target object
 {
     if(averageDistance>380) {
-        lcd.drawRect(67,2,5,16,1);
+        lcd.drawRect(67,2,5,16,1); //Draw 8 bars
 
     }
     if(averageDistance>330) {
-        lcd.drawRect(59,2,5,16,1);
+        lcd.drawRect(59,2,5,16,1); //Draw 7 bars
 
     }
     if(averageDistance>280) {
-        lcd.drawRect(51,2,5,16,1);
+        lcd.drawRect(51,2,5,16,1); //Draw 6 bars
 
     }
     if(averageDistance>230) {
-        lcd.drawRect(43,2,5,16,1);
+        lcd.drawRect(43,2,5,16,1); //Draw 5 bars
 
     }
     if(averageDistance>180) {
-        lcd.drawRect(35,2,5,16,1);
+        lcd.drawRect(35,2,5,16,1); //Draw 4 bars
 
     }
     if(averageDistance>130) {
-        lcd.drawRect(27,2,5,16,1);
+        lcd.drawRect(27,2,5,16,1);  //Draw 3 bars
 
     }
     if(averageDistance>80) {
@@ -190,7 +189,7 @@
 
     }
     if(averageDistance>30) {
-        lcd.drawRect(12,2,5,16,1); // 1 rectangle
+        lcd.drawRect(12,2,5,16,1); //Draw one rectangle
     }
     lcd.refresh();
 }
@@ -201,39 +200,39 @@
         graphArray[i] = graphArray[i-1];  //moving each element of array to right
     } 
 }
-void adjacentArrayElements()
+void adjacentArrayElements() // assigning float distance to first element of graph matrix
 {
 
     graphArray[0]= averageDistance; //array element is average distance float
-    if ((int)graphArray[0] != (int)graphArray[1]) { //if value of new array element is different to last one red led comes on
-        myled=1;
+    if ((int)graphArray[0] != (int)graphArray[1]) { //if value of current array element is different to previous one, red led and buzzer comes on ie visual and auditory alerts
+        myled=1; //red led comes on
         buzzer = delay; // duty cycle
-        buzzer.period(buzzerPeriod); //set pwm to my freq
+        buzzer.period(buzzerPeriod); //set period of buzzer to my function 
 
-    } else {
+    } else { // if no movement alerts are off
         myled=0;
         buzzer=0;
     }
 }
 
-void plotAxes()
+void plotAxes() //plotting both the x and y axis which are 2 pixels thick, i represents the pixels 
 {
     //i is pixel, plotting x axis
-    for ( int i=0; i<84; i++) {
+    for ( int i=0; i<84; i++) { // plotting x axis
         lcd.setPixel(i,46);
         lcd.setPixel(i,47);
     }
     //plotting y axis
-    for ( int i=0; i<48; i++) {
+    for ( int i=0; i<48; i++) { // plotting y axis 
         lcd.setPixel(0,i);
         lcd.setPixel(1,i);
     }
 }
-void plotDistancePoint()
+void plotDistancePoint() //function converts float distance to integer pixel
 {
 
     // i in this loop is element of the array NOT pixel
-    for (int i=0; i<82; i++) {
+    for (int i=0; i<82; i++) { // array is 82 elements long as 2 pixels are used for axes
         //x position + y position)
         int p = (int)(45-(graphArray[i]/(200/46))); //convert array element float distance to integer pixel
         //convert from float distance to integer pixel
@@ -242,3 +241,4 @@
     lcd.refresh();
 }
 
+