/*--------------------------------------------------------------------
Name:   Prof Jeff Falkinburg
Date:   <date you started working on the file>  
Course: CSCE 336 Embedded Systems (Fall 2020) 
File:   lab4_irq.cpp
HW/Lab: Lab 4, Real Time Events

Purp: Template program for Lab 4 to illustrate Real Time Events 

Doc:  <list the names of the people who you helped>
    <list the names of the people who assisted you>

Academic Integrity Statement: I certify that, while others may have 
assisted me in brain storming, debugging and validating this program, 
the program itself is my own work. I understand that submitting code 
which is the work of other individuals is a violation of the honor   
code.  I also understand that if I knowingly give my original work to 
another individual is also a violation of the honor code.
--------------------------------------------------------------------*/

#include <Arduino.h>

//LED pin 9 or Port B1
#define LED_PIN PINB1

//Pin the button is on Pin 3 or Port D3
#define BUTTON PIND3

/**
 * Setups up the timer interrupt to happen every 100 milliseconds.
 **/
void setupTimerInterrupt(){
   //Reset to defaults
  TCCR1A = TCCR1B = 0;
  // CTC with OCR1A as top
  TCCR1B |= (1 << WGM12);
  //Set clock to clk/1024
  TCCR1B |= (1 << CS12) | (1 << CS10);
  //Enable interrupt on match with OCR1A
  TIMSK1 = (1 << OCIE1A);
  
  //LAB CODE -- FILL IN
  //Configure OCR1A (the counter top) to generate an interrupt
  //every 500ms.
  //OCR1A = ;
}

void toggleLED(){
  static uint8_t on = 0;
  if(on){
    PORTB |= 1 << LED_PIN; /* Turn led on Pin 9 */
  }else{
    PORTB &= ~(1 << LED_PIN); /* Turn led off Pin 9 */
  }
  on = !on;
}

/**
 * This function is called whenever the timer interrupt match 1A
 * is generated.
 **/
ISR(TIMER1_COMPA_vect){
  //LAB CODE
  //UNCOMMENT THIS LINE TO TOGGLE ON INTERRUPT
  //toggleLED(); 
}


void setup() {
  Serial.begin(9600);
  Serial.print("Starting up...");

  //Setup the LED
  DDRB |= 1 << LED_PIN; /* Set LED as output */
  PORTB &= ~(1 << LED_PIN); /* Turn led off Pin 9 */
  
  //Setup the button
  DDRD &= ~(1 << BUTTON); /* Input Button on Pin 3 */
  PORTD |= 1 << BUTTON; /* Enable pullup on Pin 3 */
  
  Serial.println("startup complete.");
  setupTimerInterrupt();  
}

void loop() {
  static unsigned long lastTimeMS = 0;
  unsigned long currentTimeMS = 0;
  //Manually toggle the LED every 1/2 seconds
  //Comment this out when enabling the interrupt version
  currentTimeMS = millis();
  if((currentTimeMS - lastTimeMS) >= 500){
    toggleLED();
    lastTimeMS = currentTimeMS;
  }
  
  //If the button is pressed, print the ADC values
  if(!(PIND & (1 << BUTTON))){
    Serial.println("--------------------------------------------");
    Serial.println("--------------------------------------------");
    Serial.println("--------------------------------------------");
    Serial.print("The reading of analog port A0 is value: "); Serial.println(analogRead(A0));
    Serial.print("The reading of analog port A1 is value: "); Serial.println(analogRead(A1));
    Serial.print("The reading of analog port A2 is value: "); Serial.println(analogRead(A2));
    Serial.print("The reading of analog port A3 is value: "); Serial.println(analogRead(A3));
    Serial.print("The reading of analog port A4 is value: "); Serial.println(analogRead(A4));
    Serial.print("The reading of analog port A5 is value: "); Serial.println(analogRead(A5));
    Serial.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
    for(uint8_t i = 0; i < 20; i++){
        Serial.print("The reading of digital pin ");
        Serial.print(i);
        Serial.print(" has a value of: ");
        Serial.println(digitalRead(i));
    }

  }

}