Diff: main.cpp

Revision:

0:7f408d2bc038

Child:

1:e2ededd35c7b

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Thu May 05 14:58:40 2016 +0000
@@ -0,0 +1,141 @@
+/**
+@file main.cpp
+@brief Car parking sensor system which uses audio and visual alerts to assist the user
+@author Antonia Della Rocco
+*/
+
+// Allows access to all main.h information/data
+#include "main.h"
+
+/// Main function where sub functions are called
+int main()
+{
+
+    g_inches == 0; // Set initial button value to 0
+    button.mode(PullDown); // Set initial mode of button
+    button.fall(&buttonUnits); // Check falling edge
+
+    lcd.init(); // Initialise LCD screen
+    intro(); /// Call introduction function
+    wait (0.2);
+
+    while(1) {
+
+        getDistance(); /// Call distance function
+        wait (0.2);
+        indicatorLEDS(); /// Call LED function - realising I cannot set them flashing under different conditions as connected to same pin
+        wait (0.2);
+        buttonUnits(); /// Call button function
+        wait (0.2);
+        alertSound(); /// Call buzzer function
+    }
+}
+
+/// Define all functions
+/// Introduction function
+void intro()
+{
+
+    lcd.printString("Antonia's",17,1);
+    lcd.printString("Car Parking",8,2);
+    lcd.printString("System",23,3);
+    wait (1.0); // delay 1s for intro to be observed
+    lcd.clear(); // clear lcd
+}
+
+/// Function - sensor measures distance, gets average, deducts error, saves to buffer, and prints to LCD screen, also records and displays temperature reading
+void getDistance()
+{
+
+    /// additional buffers to confirm each calculation is working correctly - commented out once confirmed
+//    char buffer[14];  // each character is 6 pixels wide, screen is 84 pixels (84/6 = 14)
+//    char bufferAll[14]; // buffer for average confirmation
+//    char bufferInches[14]; // buffer for inches distance confirmation
+    char bufferTemp[14]; // buffer for temperature display
+
+    /// Create for loop to obtain average of 10 readings
+    int sumOfReadings = 0; /// Create variable for sum of readings
+    int n=0; // Iteration for n start at 0
+    for ( n=0 ; n<10 ; n++ ) { /// For loop start at 0, increase by 1 until 9 for 10 readings in total
+        int readings = srf02.getDistanceCm(); // Sensor measures distance
+        sumOfReadings += readings; // Add each measured distance to the next
+        wait(0.065); // Wait between readings
+    }
+
+    int averageDistance = (sumOfReadings / 10); /// Divide total distance by no of readings to get average
+    int error = 17; /// Set margin of error for sensor is 17cm
+
+    /// Stop calculated distance from going negative
+    if (averageDistance < error)  {
+        g_calcDistance = averageDistance;
+    } else {
+        g_calcDistance = averageDistance - error; // Calculate distance by taking away error from average distance
+    }
+    /// Get temperature reading
+    float temp = tmp102.get_temperature();
+
+    /// Convert calcuated distance to inches
+    g_calcDistanceInches = g_calcDistance * 0.3937007874;
+
+    /// Read temperature, save to buffer and print to lcd
+    float tempMemory = sprintf(bufferTemp, "T = %.2f C",temp); // saves temperature to buffer
+    lcd.printString(bufferTemp,0,4); // displays temperature buffer on lcd
+
+}
+
+/// Set LEDS function to alert user visually if range is safe or dangerous
+void indicatorLEDS()
+{
+
+    // If distance is less than/equal to 30cm red LED is ON
+    if (g_calcDistance <= 30) {
+        rLED = 0;
+    }
+    // If distance is more than 30cm red LED is OFF therefore green LED is ON
+    else if (g_calcDistance > 30) {
+        rLED = 1;
+    }
+}
+
+/// Set buzzer function to alert user audibly if range is safe or dangerous
+void soundAlert()
+{
+
+}
+
+/// Set button function to aid user preference between metric/imperial distance when parking
+void buttonUnits()
+{
+    g_inches++; // Increment unit variable by 1
+    char buffer[14];  // Buffer for cm
+    char bufferInches[14]; // Buffer for inches distance confirmation
+
+    // Press button once adds one to display
+    if (g_inches == 1) { 
+        lcd.refresh(); // Refresh lcd so it can update after button is pressed
+        float distanceInches = sprintf(bufferInches, "%.2f in",g_calcDistanceInches);
+        lcd.printString(bufferInches,0,1);
+    }
+    // Press button again adds one to display 
+    else if (g_inches == 2) {
+        lcd.refresh();
+        int distance_memory = sprintf(buffer, "%d cm",g_calcDistance); // saves distance to buffer
+        lcd.printString(buffer,0,1);
+        g_inches = 0; // Resets unit display back to beginning
+    }
+}
+
+/// Set buzzer to alert user
+void alertSound()
+{
+    buzzer.period(0.004545452);
+
+    if (g_calcDistance <= 30) { /// Less than 30 cm high pitch
+        buzzer.write(0.8);
+    }
+    else if (g_calcDistance > 30 && g_calcDistance <= 70) { // in between pitch
+        buzzer.write(0.5);
+        }
+    else if (g_calcDistance > 70) // low pitch safer distance
+        buzzer.write(0.1);
+}