eel4746_avr_piano

notes.c (5097B)

---

 /*
  *  EEL4746C - AVR Piano - Speaker Section
  *  speaker is connected to PD2 and ground
  *  15 buttons are connected to PD3-7, PC0-4, PB0-4
  *  the LCD Arduino UNO is connected to TX/RX (PD0/1)
  */
 
 #include <avr/io.h>
 #include <avr/interrupt.h>
 
 #define F_CPU		16e6
 #include <util/delay.h>
 
 #define	T1_PRESCALAR	8
 #define FREQ(f)		(16e6 / f / T1_PRESCALAR / 2)
 
 #define HIGH(sn)	((sn >> 8) & 0xff)
 #define LOW(sn)		(sn & 0xff)
 
 #define P_RX		0
 #define P_TX		1
 #define P_SPKR		2
 
 #define MARIO		50
 
 unsigned short freqs[] = {
 	// PD3-7
 	100,
 	200,
 	250,
 	300,
 	350,
 	// PB0-4
 	400,
 	450,	// middle c
 	500,
 	600,
 	700,
 	// PC0-4
 	750,
 	800,
 	850,
 	900,
 	950,
 
 	// notes
 	[MARIO] = 131,	// C3
 	262,	// C4
 	110,	// A2
 	220,	// A3
 	117,	// Bb2
 	233,	// Bb3
 
 	87,
 	175,
 	73,
 	147,
 	78,
 	156,
 
 	156,
 	147,
 	139,
 	131,
 	156,
 	147,
 	104,
 	98,
 	139,
 
 	156,
 	185,
 	175,
 	165,
 	233,
 	220,
 	208,
 	156,
 	123,
 	123,
 	110,
 	104,
 
 	['"'] = 16000,
 
 	[255] = 0	// used as a 'silent' note
 };
 
 unsigned short t_freqs[] = {
 	// PD3-7
 	FREQ(100),
 	FREQ(200),
 	FREQ(250),
 	FREQ(300),
 	FREQ(350),
 	// PB0-4
 	FREQ(400),
 	FREQ(450),	// middle c
 	FREQ(500),
 	FREQ(600),
 	FREQ(700),
 	// PC0-4
 	FREQ(750),
 	FREQ(800),
 	FREQ(850),
 	FREQ(900),
 	FREQ(950),
 
 	// notes
 	[MARIO] = FREQ(131),	// C3
 	FREQ(262),	// C4
 	FREQ(110),	// A2
 	FREQ(220),	// A3
 	FREQ(117),	// Bb2
 	FREQ(233),	// Bb3
 
 	FREQ(87),
 	FREQ(175),
 	FREQ(73),
 	FREQ(147),
 	FREQ(78),
 	FREQ(156),
 
 	FREQ(156),
 	FREQ(147),
 	FREQ(139),
 	FREQ(131),
 	FREQ(156),
 	FREQ(147),
 	FREQ(104),
 	FREQ(98),
 	FREQ(139),
 
 	FREQ(156),
 	FREQ(185),
 	FREQ(175),
 	FREQ(165),
 	FREQ(233),
 	FREQ(220),
 	FREQ(208),
 	FREQ(156),
 	FREQ(123),
 	FREQ(123),
 	FREQ(110),
 	FREQ(104),
 
 	['"'] = FREQ(16000),
 
 	[255] = 0	// used as a 'silent' note
 };
 unsigned char note = 0;
 // 0 = normal/piano mode
 // 1 = recording mode
 // 2 = mario demo
 unsigned char mode = '0';
 
 ISR (PCINT0_vect)
 {
 	// check if any button in the whole port is pressed
 	for (unsigned char i = 0; i <= 5; i++) {
 		if (PINB & (1 << i)) {
 			note = i + 5;
 			break;
 		}
 	}
 }
 
 ISR (PCINT1_vect)
 {
 	// check if any button in the whole port is pressed
 	for (unsigned char i = 0; i <= 5; i++) {
 		if (PINC & (1 << i)) {
 			note = i + 10;
 			break;
 		}
 	}
 }
 
 ISR (PCINT2_vect)
 {
 	// check if any button in the whole port is pressed
 	for (unsigned char i = 3; i <= 7; i++) {
 		if (PIND & (1 << i)) {
 			note = i - 3;
 			break;
 		}
 	}
 }
 
 void
 usart_init(void)
 {
 	// 9600 bps, TX enabled
 	UBRR0 = 103;
 	UCSR0B = 1 << TXEN0;
 	UCSR0C = (1 << UCSZ01) | (1 << UCSZ00);
 }
 
 void
 usart_send(unsigned char c)
 {
 	while (!(UCSR0A & (1 << UDRE0)));
 	UDR0 = c;
 }
 
 void
 usart_send_str(const char *c)
 {
 	for (unsigned char i = 0; c[i] != '\0'; i++)
 		usart_send(c[i]);
 }
 
 unsigned char
 usart_read(void)
 {
 	while (!(UCSR0A & (1 << RXC0)));
 	return UDR0;
 }
 
 void
 playtone(void)
 {
 	// Prepare Timer/Counter
 	TCNT1 = 1;
 	OCR1A = t_freqs[note];
 	TCCR1B |= 1 << CS11;
 
 	// Monitor OutPut Compare Flag
 	while ((TIFR1 & (1 << OCF1A)) == 0);
 
 	// Toggles port For Speaker
 	PORTD ^= 1 << P_SPKR;
 	TIFR1 |= 1 << OCF1A;
 	TCCR1B &= ~(1 << CS11);
 }
 
 void
 play_note(unsigned char _note, unsigned short _cycles)
 {
 	note = _note;
 
 	usart_send(note);
 
 	for (unsigned short i = 0; i < _cycles; i++)
 		playtone();
 
 	_delay_ms(25);
 }
 
 int
 main(void) 
 {
 	// Data Direction for Buttons, UART, Speaker
 	DDRB = 0x00;
 	DDRC = 0x00;
 	DDRD = (1 << P_TX) | (1 << P_SPKR); 
 
 	// Enabling Pin Change Interrupt for All Buttons
 	PCMSK0 = 0b00011111;
 	PCMSK1 = 0b00011111;
 	PCMSK2 = 0b11111000;
 	PCICR = (1 << PCIE0) | (1 << PCIE1) | (1 << PCIE2);
 
 	TCCR1A = 0x00; // use timer1 CTC mode
 	TCCR1B = 1 << WGM12; // already prescaled by 8 in table
 
 	sei();
 
 	usart_init();
 
 	// Sends Square wave to the Speaker When a Button is Pressed
 	unsigned short cycles = 0;
 	unsigned char tmp = 0;
 	for (unsigned char n = 0;; n = (n + 1) % 2) {
 		if (PINC & _BV(5))
 			mode = '2';
 		else if (PINB & _BV(5))
 			mode = '3';
 		else
 			mode = '0';
 
 		// check if any buttons are pressed, otherwise don't play a note
 		if (mode == '0' && ((PINB & PCMSK0) | (PINC & PCMSK1) | (PIND & PCMSK2)) == 0) {
 			// if a button was released, then send note and cycles played
 			if (cycles > 0) {
 				usart_send(tmp);
 				cycles = 0;
 			}
 			continue;
 		}
 
 		if (mode == '0') {
 			tmp = note;
 
 			playtone();
 
 			cycles = (cycles + 1) % 0xffff;
 		} else if (mode == '1') {
 			
 		} else if (mode == '3') {
 			for (unsigned char i = 0; i < 2; i++) {
 				for (unsigned char j = 0; j <= 5; j++)
 					play_note(MARIO + j, freqs[MARIO + j] * 0.3);
 				_delay_ms(1800);
 			}
 
 			for (unsigned char i = 0; i < 2; i++) {
 				for (unsigned char j = 6; j <= 11; j++)
 					play_note(MARIO + j, freqs[MARIO + j] * 0.3);
 				_delay_ms(1800);
 			}
 
 			for (unsigned char i = 12; i <= 14; i++)
 				play_note(MARIO + i, freqs[MARIO + i] * 0.3);
 			for (unsigned char i = 15; i <= 20; i++)
 				play_note(MARIO + i, freqs[MARIO + i] * 0.6);
 
 			for (unsigned char i = 21; i <= 26; i++)
 				play_note(MARIO + i, freqs[MARIO + i] * 0.3);
 			for (unsigned char i = 27; i <= 32; i++)
 				play_note(MARIO + i, freqs[MARIO + i] * 0.6);
 		}
 	}
 }