Diff: main.cpp

Revision:

0:f28e44548b08

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Sat Aug 11 08:57:24 2018 +0000
@@ -0,0 +1,153 @@
+#include "mbed.h"
+#include "C12832.h"
+
+DigitalOut trig(p21); //definition of the input signal.
+DigitalIn echo(p22); //definition of the input signal.
+
+DigitalOut led1(LED1); // defines the led 1 used to show the trigger signal is happening.
+DigitalOut led2(LED2); // defines the led 2 used to show the echo signal is happening.
+DigitalOut led4(LED4); //defines the led 1 used to show the buzzer is turned on or off.
+
+C12832 lcd(p5, p7, p6, p8, p11); //Definition of LCD & Pins.
+
+Timer sonar; //definition of the sonar timer.
+
+PwmOut spker (p26); //Definition of the speaker.
+
+PwmOut r (p23); //Definition of the red led.
+PwmOut g (p24); //Definition of the green led.
+PwmOut b (p25); //Definition of the blue led.
+
+InterruptIn button(p14); //interrupt used to turn on/off buzzer. "calls function to flip buzzstart".
+Timer debounce; //debounces button timer.
+
+int measurement; //defines the measurement variable.
+
+int offset = 0; //definition of the sonar timer offset.
+
+float inMin = 200; //minimum value readable in mm.
+float inMax = 4000; //maximum readable value in mm.
+float outMin = 0; //minimum mapped output value.
+float outMax = 1; //maximum mapped output value.
+float mapping = 0; //mapping value.
+
+bool buzzstart; // value flipped from o-1 to turn on off buzzer.
+
+float spkerVal=0.5; //initial pwm out value.
+
+//ranges used for buzzer.
+int range1Min = 300;
+int range2Min = 800;
+int range3Min = 1200;
+
+//ranges used for speaker output.
+int spkroutnear= 1000;
+int spkroutmid= 600;
+int spkroutfar= 200;
+
+float mapped_led() //function to create the map value for the leds.
+{
+    //mapping calculation for the measured distance to a float value between 0 and 1 used for RGB colour gradient shifts colour from green to red as the distance changes. I could have done this more directly but the mapping calculation is a nice bit of code to have to map one range of values to another.
+    mapping = ((measurement - inMin) * (outMax - outMin) / (inMax - inMin) +  outMin);
+//Caps the value for the RGBs between 0 and 1
+    if (mapping < 0.00f) { //if statement less than 0 return 0.
+        return 0;
+    } else if (mapping > 1.00f) { //if statement greater than 1 return 1.
+        return 1;
+    } else {
+        return mapping; //value to return between 0 and 1.
+    }
+}
+
+void ledCntrl() //function to control the leds pwm value on the application board.
+{
+    r=mapped_led(); //sets the value of the common anode RGB red to a duty cycle equal to the mapped value.
+    g=1-mapped_led (); //sets the value of the common anode RGB green to a duty cycle of 1 less the mapped value.
+
+    if  (buzzstart==1) { //condition based on bool value used to set the on condition of the onboard speaker.
+        if (measurement <= range1Min) { //if the measurement from the sensor is less than or equal to the lower value then;
+            spker.period(1.0/spkroutnear); //creates the Pwm  out for the speaker/frequency to make the sound.
+            spker=spkerVal; // this is the value for the speaker duty cycle output 0 would turn the speaker off.
+        }
+        if (measurement >= range1Min && measurement <= range2Min) { //condition if measurement is less than/equal to  range 1 and less than/equal to range 2 do the following;
+            spker.period(1.0/spkroutmid); //creates the Pwm  out for the speaker/frequency to make the sound.
+            spker=spkerVal; // this is the value for the speaker duty cycle output 0 would turn the speaker off.
+        }
+        if (measurement >= range2Min && measurement <= range3Min) { //condition if measurement is greater than/equal to  range 2 and less than/equal to range 3 do the following;
+            spker.period(1.0/spkroutfar); //creates the Pwm  out for the speaker/frequency to make the sound.
+            spker=spkerVal; // this is the value for the speaker duty cycle output 0 would turn the speaker off.
+        } else if (measurement > range3Min) {//condition if measurement is greater than range 3 do the following;
+            spker = 0; //turns off the speaker.
+        }
+    } else if (measurement > range3Min) { //condition if measurement is greater than range 3 do the following;
+        spker = 0; //turns off the speaker.
+    }
+}
+void buzzCntrl() //function to control the bool value used to activate the buzzer.
+{
+    if (debounce.read_ms() >(200)) { //this conditional statement checks to see if the debounce time is greater than x milliseconds. It ignores any detected presses inside of this time.
+        debounce.reset(); //this will reset the button press timer allowing for another press to happen and the debouncing timer to start again.
+        led4=!led4; //flips the condition of led 4.
+        buzzstart = led4.read(); // links the state of buzzstart to led 4.
+    }
+}
+void printdim()   //LCD Print Function
+{
+    lcd.cls(); //Clears the LCD
+    lcd.locate(2,15); //Location to be used for measurement information in mm.
+    lcd.printf("Measurement %d mm" ,measurement); //send the measurement to the lcd for display.
+}
+void measure_offset () //allows for the measure of software polling timer delay in microseconds used to correct possible errors in the measurement times due to the delay.
+{
+    while (echo==2) {}; // loops while the value of echo is 2, then following happens.
+    led2 = 0; // condition of led 2 is set to 0.
+    sonar.stop(); // the timer sonar is stopped.
+    offset = sonar.read_us(); // reads the timer
+}
+void take_measure()   //measure distance between 2cm and 4m.
+{
+    int A_sum = 0; //sets the initial value for the average sum of the readings.
+
+    while(1) { //Loop to read Sonar distance values, scale, and print values.
+        trig = 1; // trigger sonar to send a ping
+        led1 = trig; // led1 was set to trigger
+        led2 = 0; // led 2 was set to 0
+        sonar.reset(); //the sonar timer was reset.
+        wait_us(10.0); // wait period for trigger out signal.
+        trig = 0;  // turns of the trigger signal
+        led1 = trig; //sets the led1 to the value of the trigger.
+//wait for echo high
+        while (echo==0) {}; // loop while the echo = o, then do the following.
+        led2=echo; // sets led 2 equal to the state of echo.
+        sonar.start(); //echo high, so start timer
+        while (echo==1) {}; //loop while echo = 1, then do the following;
+        sonar.stop(); //stop timer
+        for (int A = 0; A < 5; ++A) { //for the increments of I, read the sonar and sum the values, each reading has the software overhead timer delay subtracted and is scaled to mm
+            A_sum += (((sonar.read_us()-offset)/58.0)*10); //value of the sum.
+        }
+        measurement = A_sum/5.00f; //average of the readings by dividing the sum by the number of reading “5”.
+        led2 = 0; //sets the value of the led to 0.
+        wait(0.2); //loop wait period.
+        break; // breaks out of the loop.
+    }
+}
+int main() //main function of the application.
+{
+    r=1; //initial value of the red led.
+    g=1; //initial value of the red green.
+    b=1; //initial value of the blue led.
+    sonar.reset();// resets the value of the sonar.
+    sonar.start(); //starts the sonar timer.
+    measure_offset(); //calls the measure offset value.
+    button.rise(&buzzCntrl); //interrupt in call the buzzer control function.
+    debounce.start(); //starts the button debounce timer.
+
+    while(1) { // main while loop.
+        take_measure(); //calls the measure function.
+        mapped_led(); // calls the value mapping function for the leds.
+        printdim(); //calls the print function to print the dimensions out the to the led screen.
+        ledCntrl(); // calls the led control function.
+    }
+}
+
+