1 files changed, 70 insertions, 36 deletions

diff --git a/final_project/main.c b/final_project/main.c
index f301ef5..926cb99 100644
--- a/final_project/main.c
+++ b/final_project/main.c
@@ -18,15 +18,45 @@
 volatile int seconds_remaining; //will be used by ISR
 
 #define SPEAKER_PORT PORTE
-#define SPEAKER_PIN 4 //rename?
+#define SPEAKER_PIN 4 
 #define ELEMENT_COUNT 7
 
-//TODO get_button and display_element unnecessarily complex
+
+
+
+/** GETTING/DISPLAYING ELEMENTS
+  * Two of the LEDs are connected to the RX1/TX1 pins, used for serial.
+  * Because of this, there's 7 possible elements.
+  * Here's how elements (guesses) are retrieved from buttons and displayed on LEDs:
+  
+  * If the button is on PINA, the element is set to the reading from PINA, 
+  * unmodified (aside from the two invalid buttons being masked).
+  * this allows easy LED outputting.
+  
+  * If the button is the single one connected to PORTE,
+  * the 2nd bit is set. When displaying elements, we assume
+  * the second bit is the middle PORTE LED.
+  
+  */
+
 uint8_t get_button() {
-	if(~PINE & (1 << 6)) return (1 << 2);
-	return ((~PINA) & ~(0b1100)); //TODO clean up
+	//debouncing is done by waiting for the user to stop pressing the button,
+	//then waiting an amount of time for the bouncing to stop.
+	const double debounce_wait = 100.0;
+	if(~PINE & (1 << 6)) {
+		while((~PINE & (1<<6)));
+		_delay_ms(debounce_wait);
+		return (1 << 2);
+	}
+	uint8_t porta_state = (~PINA) & ~(0b1100);
+	if(porta_state) {
+		while(PINA != 0xff);
+		_delay_ms(debounce_wait);	
+	}
+	return porta_state;
 }
 
+//for documentation see above paragraph
 void display_element(uint8_t element, unsigned int time) {
 	uint8_t portd_state = 0;
 	uint8_t porte_state = 0;
@@ -42,23 +72,19 @@ void display_element(uint8_t element, unsigned int time) {
 }
 
 void init_io() {
+	//initilize IO registers
+	//Buttons
 	DDRA = 0x00;
 	PORTA = 0xff;
 	
-	DDRD = 0xff; 
+	//LEDs
+	DDRD = 0xff;
 	PORTD = 0xff;
 	
-	DDRE = (1 << 4) | (1 << 5);
+	//speaker and middle LED
+	DDRE = (1 << 4) | (1 << 5); 
 	PORTE = 0xff;	
 }
-void test_timer() {
-	for(;;)	{
-		usart_txstr("timer test\n");
-		start_timer();
-		while(!timer_done());
-		stop_timer();
-	}
-}
 
 int main(void) {
 	cli();
@@ -78,6 +104,7 @@ int main(void) {
 		"2. Moderate\n"
 		"3. Give me pain.");
 
+		//ask until valid input
 		while((level > 3) || (level < 1)) level = (int)(usart_rxt_blocking() - '0');
 		
 	
@@ -91,7 +118,7 @@ int main(void) {
 			double score;
 			uint8_t element_list[5]; // TODO
 	
-	
+			//this is where the level properties are set depending on level
 			switch(level) {
 				case 1:
 					sets = 3;
@@ -117,31 +144,39 @@ int main(void) {
 			}
 
 	
-			//main level
+			//it's easier to make a variable to count the number of guesses (max_score)
+			//and increment current_score after each correct guess to calculate total score
+			//as the number of elements per set scale.
 			int max_score = 0;
-			int current_score = 0;
+			int current_score = 0; 
 			for(int set = 0; set < sets; set++) {
+				//scale from elements_min (first set) to elements_max (last set)
 				int elements = elements_min + ceil(((elements_max - elements_min) / (float)(sets - 1)) * set);
-				//generate, display elements
+				
+				//randomly get, display elements
 				for(int element = 0; element < elements; element++) {
 					uint8_t element_bit = (rand() % ELEMENT_COUNT);
-					if(element_bit == 3) element_bit = 7;
+					// button 3 should never be pressed, so if 3 is randomly generated,
+					// we make it the last LED. We only generate 7 potential elements. 
+					if(element_bit == 3) element_bit = 7;  
 					uint8_t this_element = 1 << element_bit;
 					usart_txt('\n');
 					usart_txt(element_bit + '0');
 					usart_txt('\n');
-					element_list[element] = this_element; // could optimize
+					element_list[element] = this_element; //will be compared to guesses later
 					display_element(this_element, display_time);
 					
 				}
-				//get elements
+				//get elements from buttono presses
+				//we'll poll the timer to see if a second has passed
+				//as timer only supports a max of 0xffff * (1024 / 16000000) seconds
 				seconds_remaining = response_time;
 				start_timer();
 				uint16_t guess;
 				for(int element = 0; element < elements; element++) {
-					usart_txstr("\ngot element, waiting...\n");
+					guess = 0;
 					do {
-						if(timer_done()) {
+						if(timer_done()) { //accounts for seconds passed
 							seconds_remaining--;
 							stop_timer(); //TODO only need one function
 							start_timer();
@@ -149,7 +184,6 @@ int main(void) {
 						}
 						else { guess = get_button(); }
 					} while((!guess) && (seconds_remaining > 0));
-					_delay_ms(250); //prevent double press
 					max_score++;
 					if(guess == element_list[element]) {
 						current_score++;
@@ -160,25 +194,19 @@ int main(void) {
 					}
 				}	
 			}
+			//where we check the score. Score is calculated per level.
+			//If score under 80, we break back to the menu.
 			score = (float)current_score / max_score;
 			if(score >= .8) { 
 				level++;
 				usart_txstr("\nnext level\n"); 
-				}
+			}
 			else { 
 				loose(); 
 				break;
 			}
 		}
-		if(level >= 3) win();
-	}
-}
-
-//timer interrupt
-ISR(TIMER1_COMPA_vect) {
-	if(seconds_remaining-- > 0) return;
-	for(;;) {
-		beep();
+		if(level >= 3) win(); //you win if you get past level 3
 	}
 }
 
@@ -206,8 +234,14 @@ void loose() {
 	beep(294., .5);
 }
 
-
-//TODO move somewhere else
+/** can handle specific frequencies for a durientation of time.
+ * speaker_ms is caculated by taking the period, dividing by 2
+ * (as we need to flip speaker state once per cycle)
+ * then multiplies it by 1000 to convert to ms for _delay_ms.
+ * We control how long its played by making it loop,
+ * loop count is durientation of note / period. 
+ * loop_count will be off by a max of 1 period.
+ **/
 void beep(double frequency, double durientation) {
 	double speaker_ms = ((1.0 / frequency) / 2.0) * 1000.0; //TODO clean up
 	int loop_count = durientation / (1.0 / frequency);