/* $Id: Tone.cpp 119 2010-07-17 18:56:36Z bhagman@roguerobotics.com $
A Tone Generator Library
Written by Brett Hagman
http://www.roguerobotics.com/
bhagman@roguerobotics.com
This library is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see .
Made Arduino 1.0 Complient on Feb 20, 2012 by Michael Pilcher
*************************************************/
#include
#include
#include
#include
#include "Tone.h"
#if defined(__AVR_ATmega8__)
#define TCCR2A TCCR2
#define TCCR2B TCCR2
#define COM2A1 COM21
#define COM2A0 COM20
#define OCR2A OCR2
#define TIMSK2 TIMSK
#define OCIE2A OCIE2
#define TIMER2_COMPA_vect TIMER2_COMP_vect
#define TIMSK1 TIMSK
#endif
// timerx_toggle_count:
// > 0 - duration specified
// = 0 - stopped
// < 0 - infinitely (until stop() method called, or new play() called)
#if !defined(__AVR_ATmega8__)
volatile int32_t timer0_toggle_count;
volatile uint8_t *timer0_pin_port;
volatile uint8_t timer0_pin_mask;
#endif
volatile int32_t timer1_toggle_count;
volatile uint8_t *timer1_pin_port;
volatile uint8_t timer1_pin_mask;
volatile int32_t timer2_toggle_count;
volatile uint8_t *timer2_pin_port;
volatile uint8_t timer2_pin_mask;
#if defined(__AVR_ATmega1280__)
volatile int32_t timer3_toggle_count;
volatile uint8_t *timer3_pin_port;
volatile uint8_t timer3_pin_mask;
volatile int32_t timer4_toggle_count;
volatile uint8_t *timer4_pin_port;
volatile uint8_t timer4_pin_mask;
volatile int32_t timer5_toggle_count;
volatile uint8_t *timer5_pin_port;
volatile uint8_t timer5_pin_mask;
#endif
#if defined(__AVR_ATmega1280__)
#define AVAILABLE_TONE_PINS 6
// Leave timers 1, and zero to last.
const uint8_t PROGMEM tone_pin_to_timer_PGM[] = { 2, 3, 4, 5, 1, 0 };
#elif defined(__AVR_ATmega8__)
#define AVAILABLE_TONE_PINS 2
const uint8_t PROGMEM tone_pin_to_timer_PGM[] = { 2, 1 };
#else
#define AVAILABLE_TONE_PINS 3
// Leave timer 0 to last.
const uint8_t PROGMEM tone_pin_to_timer_PGM[] = { 2, 1, 0 };
#endif
// Initialize our pin count
uint8_t Tone::_tone_pin_count = 0;
void Tone::begin(uint8_t tonePin)
{
if (_tone_pin_count < AVAILABLE_TONE_PINS)
{
_pin = tonePin;
_timer = pgm_read_byte(tone_pin_to_timer_PGM + _tone_pin_count);
_tone_pin_count++;
// Set timer specific stuff
// All timers in CTC mode
// 8 bit timers will require changing prescalar values,
// whereas 16 bit timers are set to either ck/1 or ck/64 prescalar
switch (_timer)
{
#if !defined(__AVR_ATmega8__)
case 0:
// 8 bit timer
TCCR0A = 0;
TCCR0B = 0;
bitWrite(TCCR0A, WGM01, 1);
bitWrite(TCCR0B, CS00, 1);
timer0_pin_port = portOutputRegister(digitalPinToPort(_pin));
timer0_pin_mask = digitalPinToBitMask(_pin);
break;
#endif
case 1:
// 16 bit timer
TCCR1A = 0;
TCCR1B = 0;
bitWrite(TCCR1B, WGM12, 1);
bitWrite(TCCR1B, CS10, 1);
timer1_pin_port = portOutputRegister(digitalPinToPort(_pin));
timer1_pin_mask = digitalPinToBitMask(_pin);
break;
case 2:
// 8 bit timer
TCCR2A = 0;
TCCR2B = 0;
bitWrite(TCCR2A, WGM21, 1);
bitWrite(TCCR2B, CS20, 1);
timer2_pin_port = portOutputRegister(digitalPinToPort(_pin));
timer2_pin_mask = digitalPinToBitMask(_pin);
break;
#if defined(__AVR_ATmega1280__)
case 3:
// 16 bit timer
TCCR3A = 0;
TCCR3B = 0;
bitWrite(TCCR3B, WGM32, 1);
bitWrite(TCCR3B, CS30, 1);
timer3_pin_port = portOutputRegister(digitalPinToPort(_pin));
timer3_pin_mask = digitalPinToBitMask(_pin);
break;
case 4:
// 16 bit timer
TCCR4A = 0;
TCCR4B = 0;
bitWrite(TCCR4B, WGM42, 1);
bitWrite(TCCR4B, CS40, 1);
timer4_pin_port = portOutputRegister(digitalPinToPort(_pin));
timer4_pin_mask = digitalPinToBitMask(_pin);
break;
case 5:
// 16 bit timer
TCCR5A = 0;
TCCR5B = 0;
bitWrite(TCCR5B, WGM52, 1);
bitWrite(TCCR5B, CS50, 1);
timer5_pin_port = portOutputRegister(digitalPinToPort(_pin));
timer5_pin_mask = digitalPinToBitMask(_pin);
break;
#endif
}
}
else
{
// disabled
_timer = -1;
}
}
// frequency (in hertz) and duration (in milliseconds).
void Tone::play(uint16_t frequency, uint32_t duration)
{
uint8_t prescalarbits = 0b001;
int32_t toggle_count = 0;
uint32_t ocr = 0;
if (_timer >= 0)
{
// Set the pinMode as OUTPUT
pinMode(_pin, OUTPUT);
// if we are using an 8 bit timer, scan through prescalars to find the best fit
if (_timer == 0 || _timer == 2)
{
ocr = F_CPU / frequency / 2 - 1;
prescalarbits = 0b001; // ck/1: same for both timers
if (ocr > 255)
{
ocr = F_CPU / frequency / 2 / 8 - 1;
prescalarbits = 0b010; // ck/8: same for both timers
if (_timer == 2 && ocr > 255)
{
ocr = F_CPU / frequency / 2 / 32 - 1;
prescalarbits = 0b011;
}
if (ocr > 255)
{
ocr = F_CPU / frequency / 2 / 64 - 1;
prescalarbits = _timer == 0 ? 0b011 : 0b100;
if (_timer == 2 && ocr > 255)
{
ocr = F_CPU / frequency / 2 / 128 - 1;
prescalarbits = 0b101;
}
if (ocr > 255)
{
ocr = F_CPU / frequency / 2 / 256 - 1;
prescalarbits = _timer == 0 ? 0b100 : 0b110;
if (ocr > 255)
{
// can't do any better than /1024
ocr = F_CPU / frequency / 2 / 1024 - 1;
prescalarbits = _timer == 0 ? 0b101 : 0b111;
}
}
}
}
#if !defined(__AVR_ATmega8__)
if (_timer == 0)
TCCR0B = (TCCR0B & 0b11111000) | prescalarbits;
else
#endif
TCCR2B = (TCCR2B & 0b11111000) | prescalarbits;
}
else
{
// two choices for the 16 bit timers: ck/1 or ck/64
ocr = F_CPU / frequency / 2 - 1;
prescalarbits = 0b001;
if (ocr > 0xffff)
{
ocr = F_CPU / frequency / 2 / 64 - 1;
prescalarbits = 0b011;
}
if (_timer == 1)
TCCR1B = (TCCR1B & 0b11111000) | prescalarbits;
#if defined(__AVR_ATmega1280__)
else if (_timer == 3)
TCCR3B = (TCCR3B & 0b11111000) | prescalarbits;
else if (_timer == 4)
TCCR4B = (TCCR4B & 0b11111000) | prescalarbits;
else if (_timer == 5)
TCCR5B = (TCCR5B & 0b11111000) | prescalarbits;
#endif
}
// Calculate the toggle count
if (duration > 0)
{
toggle_count = 2 * frequency * duration / 1000;
}
else
{
toggle_count = -1;
}
// Set the OCR for the given timer,
// set the toggle count,
// then turn on the interrupts
switch (_timer)
{
#if !defined(__AVR_ATmega8__)
case 0:
OCR0A = ocr;
timer0_toggle_count = toggle_count;
bitWrite(TIMSK0, OCIE0A, 1);
break;
#endif
case 1:
OCR1A = ocr;
timer1_toggle_count = toggle_count;
bitWrite(TIMSK1, OCIE1A, 1);
break;
case 2:
OCR2A = ocr;
timer2_toggle_count = toggle_count;
bitWrite(TIMSK2, OCIE2A, 1);
break;
#if defined(__AVR_ATmega1280__)
case 3:
OCR3A = ocr;
timer3_toggle_count = toggle_count;
bitWrite(TIMSK3, OCIE3A, 1);
break;
case 4:
OCR4A = ocr;
timer4_toggle_count = toggle_count;
bitWrite(TIMSK4, OCIE4A, 1);
break;
case 5:
OCR5A = ocr;
timer5_toggle_count = toggle_count;
bitWrite(TIMSK5, OCIE5A, 1);
break;
#endif
}
}
}
void Tone::stop()
{
switch (_timer)
{
#if !defined(__AVR_ATmega8__)
case 0:
TIMSK0 &= ~(1 << OCIE0A);
break;
#endif
case 1:
TIMSK1 &= ~(1 << OCIE1A);
break;
case 2:
TIMSK2 &= ~(1 << OCIE2A);
break;
#if defined(__AVR_ATmega1280__)
case 3:
TIMSK3 &= ~(1 << OCIE3A);
break;
case 4:
TIMSK4 &= ~(1 << OCIE4A);
break;
case 5:
TIMSK5 &= ~(1 << OCIE5A);
break;
#endif
}
digitalWrite(_pin, 0);
}
bool Tone::isPlaying(void)
{
bool returnvalue = false;
switch (_timer)
{
#if !defined(__AVR_ATmega8__)
case 0:
returnvalue = (TIMSK0 & (1 << OCIE0A));
break;
#endif
case 1:
returnvalue = (TIMSK1 & (1 << OCIE1A));
break;
case 2:
returnvalue = (TIMSK2 & (1 << OCIE2A));
break;
#if defined(__AVR_ATmega1280__)
case 3:
returnvalue = (TIMSK3 & (1 << OCIE3A));
break;
case 4:
returnvalue = (TIMSK4 & (1 << OCIE4A));
break;
case 5:
returnvalue = (TIMSK5 & (1 << OCIE5A));
break;
#endif
}
return returnvalue;
}
#if !defined(__AVR_ATmega8__)
ISR(TIMER0_COMPA_vect)
{
if (timer0_toggle_count != 0)
{
// toggle the pin
*timer0_pin_port ^= timer0_pin_mask;
if (timer0_toggle_count > 0)
timer0_toggle_count--;
}
else
{
TIMSK0 &= ~(1 << OCIE0A); // disable the interrupt
*timer0_pin_port &= ~(timer0_pin_mask); // keep pin low after stop
}
}
#endif
ISR(TIMER1_COMPA_vect)
{
if (timer1_toggle_count != 0)
{
// toggle the pin
*timer1_pin_port ^= timer1_pin_mask;
if (timer1_toggle_count > 0)
timer1_toggle_count--;
}
else
{
TIMSK1 &= ~(1 << OCIE1A); // disable the interrupt
*timer1_pin_port &= ~(timer1_pin_mask); // keep pin low after stop
}
}
ISR(TIMER2_COMPA_vect)
{
int32_t temp_toggle_count = timer2_toggle_count;
if (temp_toggle_count != 0)
{
// toggle the pin
*timer2_pin_port ^= timer2_pin_mask;
if (temp_toggle_count > 0)
temp_toggle_count--;
}
else
{
TIMSK2 &= ~(1 << OCIE2A); // disable the interrupt
*timer2_pin_port &= ~(timer2_pin_mask); // keep pin low after stop
}
timer2_toggle_count = temp_toggle_count;
}
#if defined(__AVR_ATmega1280__)
ISR(TIMER3_COMPA_vect)
{
if (timer3_toggle_count != 0)
{
// toggle the pin
*timer3_pin_port ^= timer3_pin_mask;
if (timer3_toggle_count > 0)
timer3_toggle_count--;
}
else
{
TIMSK3 &= ~(1 << OCIE3A); // disable the interrupt
*timer3_pin_port &= ~(timer3_pin_mask); // keep pin low after stop
}
}
ISR(TIMER4_COMPA_vect)
{
if (timer4_toggle_count != 0)
{
// toggle the pin
*timer4_pin_port ^= timer4_pin_mask;
if (timer4_toggle_count > 0)
timer4_toggle_count--;
}
else
{
TIMSK4 &= ~(1 << OCIE4A); // disable the interrupt
*timer4_pin_port &= ~(timer4_pin_mask); // keep pin low after stop
}
}
ISR(TIMER5_COMPA_vect)
{
if (timer5_toggle_count != 0)
{
// toggle the pin
*timer5_pin_port ^= timer5_pin_mask;
if (timer5_toggle_count > 0)
timer5_toggle_count--;
}
else
{
TIMSK5 &= ~(1 << OCIE5A); // disable the interrupt
*timer5_pin_port &= ~(timer5_pin_mask); // keep pin low after stop
}
}
#endif