/* Tone.cpp A Tone Generator Library Written by Brett Hagman This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA Version Modified By Date Comments ------- ----------- -------- -------- 0001 B Hagman 09/08/02 Initial coding 0002 B Hagman 09/08/18 Multiple pins 0003 B Hagman 09/08/18 Moved initialization from constructor to begin() 0004 B Hagman 09/09/26 Fixed problems with ATmega8 0005 B Hagman 09/11/23 Scanned prescalars for best fit on 8 bit timers 09/11/25 Changed pin toggle method to XOR 09/11/25 Fixed timer0 from being excluded *************************************************/ #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 long timer0_toggle_count; volatile uint8_t *timer0_pin_port[2]; volatile uint8_t timer0_pin_mask[2]; #endif volatile long timer1_toggle_count; volatile uint8_t *timer1_pin_port[2]; volatile uint8_t timer1_pin_mask[2]; volatile long timer2_toggle_count; volatile uint8_t *timer2_pin_port[2]; volatile uint8_t timer2_pin_mask[2]; #if defined(__AVR_ATmega1280__) volatile long timer3_toggle_count; volatile uint8_t *timer3_pin_port[2]; volatile uint8_t timer3_pin_mask[2]; volatile long timer4_toggle_count; volatile uint8_t *timer4_pin_port[2]; volatile uint8_t timer4_pin_mask[2]; volatile long timer5_toggle_count; volatile uint8_t *timer5_pin_port[2]; volatile uint8_t timer5_pin_mask[2]; #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, uint8_t tonePinDifferentialDrive) { if (_tone_pin_count < AVAILABLE_TONE_PINS) { _pin[0] = tonePin; if (tonePinDifferentialDrive == 255) { _pin[1] = _pin[0]; } else { _pin[1] = tonePinDifferentialDrive; } _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[0] = portOutputRegister(digitalPinToPort(_pin[0])); timer0_pin_port[1] = portOutputRegister(digitalPinToPort(_pin[1])); timer0_pin_mask[0] = digitalPinToBitMask(_pin[0]); timer0_pin_mask[1] = digitalPinToBitMask(_pin[1]); break; #endif case 1: // 16 bit timer TCCR1A = 0; TCCR1B = 0; bitWrite(TCCR1B, WGM12, 1); bitWrite(TCCR1B, CS10, 1); timer1_pin_port[0] = portOutputRegister(digitalPinToPort(_pin[0])); timer1_pin_port[1] = portOutputRegister(digitalPinToPort(_pin[1])); timer1_pin_mask[0] = digitalPinToBitMask(_pin[0]); timer1_pin_mask[1] = digitalPinToBitMask(_pin[1]); break; case 2: // 8 bit timer TCCR2A = 0; TCCR2B = 0; bitWrite(TCCR2A, WGM21, 1); bitWrite(TCCR2B, CS20, 1); timer2_pin_port[0] = portOutputRegister(digitalPinToPort(_pin[0])); timer2_pin_port[1] = portOutputRegister(digitalPinToPort(_pin[1])); timer2_pin_mask[0] = digitalPinToBitMask(_pin[0]); timer2_pin_mask[1] = digitalPinToBitMask(_pin[1]); 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[0] = portOutputRegister(digitalPinToPort(_pin[0])); timer3_pin_port[1] = portOutputRegister(digitalPinToPort(_pin[1])); timer3_pin_mask[0] = digitalPinToBitMask(_pin[0]); timer3_pin_mask[1] = digitalPinToBitMask(_pin[1]); break; case 4: // 16 bit timer TCCR4A = 0; TCCR4B = 0; bitWrite(TCCR4B, WGM42, 1); bitWrite(TCCR4B, CS40, 1); timer4_pin_port[0] = portOutputRegister(digitalPinToPort(_pin[0])); timer4_pin_port[1] = portOutputRegister(digitalPinToPort(_pin[1])); timer4_pin_mask[0] = digitalPinToBitMask(_pin[0]); timer4_pin_mask[1] = digitalPinToBitMask(_pin[1]); break; case 5: // 16 bit timer TCCR5A = 0; TCCR5B = 0; bitWrite(TCCR5B, WGM52, 1); bitWrite(TCCR5B, CS50, 1); timer5_pin_port[0] = portOutputRegister(digitalPinToPort(_pin[0])); timer5_pin_port[1] = portOutputRegister(digitalPinToPort(_pin[1])); timer5_pin_mask[0] = digitalPinToBitMask(_pin[0]); timer5_pin_mask[1] = digitalPinToBitMask(_pin[1]); break; #endif } } else { // disabled _timer = -1; } } // frequency (in hertz) and duration (in milliseconds). void Tone::play(unsigned int frequency, unsigned long duration) { uint8_t prescalarbits = 0b001; long toggle_count = 0; uint32_t ocr = 0; if (_timer >= 0) { // Set the pinMode as OUTPUT pinMode(_pin[0], OUTPUT); pinMode(_pin[1], 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 = prescalarbits; else #endif TCCR2B = 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 1: bitWrite(TIMSK1, OCIE1A, 0); break; case 2: bitWrite(TIMSK2, OCIE2A, 0); break; #else case 0: TIMSK0 = 0; break; case 1: TIMSK1 = 0; break; case 2: TIMSK2 = 0; break; #endif #if defined(__AVR_ATmega1280__) case 3: TIMSK3 = 0; break; case 4: TIMSK4 = 0; break; case 5: TIMSK5 = 0; break; #endif } digitalWrite(_pin[0], 0); if (_pin[1] != _pin[0]) { digitalWrite(_pin[1], 1); } } bool Tone::isPlaying(void) { bool returnvalue = false; switch (_timer) { #if !defined(__AVR_ATmega8__) case 0: returnvalue = (timer0_toggle_count > 0) || (TIMSK0 & (1 << OCIE0A)); break; #endif case 1: returnvalue = (timer1_toggle_count > 0) || (TIMSK1 & (1 << OCIE1A)); break; case 2: returnvalue = (timer2_toggle_count > 0) || (TIMSK2 & (1 << OCIE2A)); break; #if defined(__AVR_ATmega1280__) case 3: returnvalue = (timer3_toggle_count > 0) || (TIMSK3 & (1 << OCIE3A)); break; case 4: returnvalue = (timer4_toggle_count > 0) || (TIMSK4 & (1 << OCIE4A)); break; case 5: returnvalue = (timer5_toggle_count > 0) || (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[0] ^= timer0_pin_mask[0]; if (timer0_pin_mask[0] != timer0_pin_mask[1]) { *timer0_pin_port[1] ^= timer0_pin_mask[1]; } if (timer0_toggle_count > 0) timer0_toggle_count--; } else { TIMSK0 = 0; // disable the interrupt *timer0_pin_port[0] &= ~(timer0_pin_mask[0]); // keep pin low after stop if (timer0_pin_mask[0] != timer0_pin_mask[1]) { *timer0_pin_port[1] &= ~(timer0_pin_mask[1]); // keep pin low after stop } } } #endif ISR(TIMER1_COMPA_vect) { if (timer1_toggle_count != 0) { // toggle the pin *timer1_pin_port[0] ^= timer1_pin_mask[0]; if (timer1_pin_mask[0] != timer1_pin_mask[1]) { *timer1_pin_port[1] ^= timer1_pin_mask[1]; } if (timer1_toggle_count > 0) timer1_toggle_count--; } else { TIMSK1 = 0; // disable the interrupt *timer1_pin_port[0] &= ~(timer1_pin_mask[0]); // keep pin low after stop if (timer1_pin_mask[0] != timer1_pin_mask[1]) { *timer1_pin_port[1] &= ~(timer1_pin_mask[1]); // keep pin low after stop } } } ISR(TIMER2_COMPA_vect) { if (timer2_toggle_count != 0) { // toggle the pin *timer2_pin_port[0] ^= timer2_pin_mask[0]; if (timer2_pin_mask[0] != timer2_pin_mask[1]) { *timer2_pin_port[1] ^= timer2_pin_mask[1]; } if (timer2_toggle_count > 0) timer2_toggle_count--; } else { TIMSK2 = 0; // disable the interrupt *timer2_pin_port[0] &= ~(timer2_pin_mask[0]); // keep pin low after stop if (timer2_pin_mask[0] != timer2_pin_mask[1]) { *timer2_pin_port[1] &= ~(timer2_pin_mask[1]); // keep pin low after stop } } } #if defined(__AVR_ATmega1280__) ISR(TIMER3_COMPA_vect) { if (timer3_toggle_count != 0) { // toggle the pin *timer3_pin_port[0] ^= timer3_pin_mask[0]; if (timer3_pin_mask[0] != timer3_pin_mask[1]) { *timer3_pin_port[1] ^= timer3_pin_mask[1]; } if (timer3_toggle_count > 0) timer3_toggle_count--; } else { TIMSK3 = 0; // disable the interrupt *timer3_pin_port[0] &= ~(timer3_pin_mask[0]); // keep pin low after stop if (timer3_pin_mask[0] != timer3_pin_mask[1]) { *timer3_pin_port[1] &= ~(timer3_pin_mask[1]); // keep pin low after stop } } } ISR(TIMER4_COMPA_vect) { if (timer4_toggle_count != 0) { // toggle the pin *timer4_pin_port[0] ^= timer4_pin_mask[0]; if (timer4_pin_mask[0] != timer4_pin_mask[1]) { *timer4_pin_port[1] ^= timer4_pin_mask[1]; } if (timer4_toggle_count > 0) timer4_toggle_count--; } else { TIMSK4 = 0; // disable the interrupt *timer4_pin_port[0] &= ~(timer4_pin_mask[0]); // keep pin low after stop if (timer4_pin_mask[0] != timer4_pin_mask[1]) { *timer4_pin_port[1] &= ~(timer4_pin_mask[1]); // keep pin low after stop } } } ISR(TIMER5_COMPA_vect) { if (timer5_toggle_count != 0) { // toggle the pin *timer5_pin_port[0] ^= timer5_pin_mask[0]; if (timer5_pin_mask[0] != timer5_pin_mask[1]) { *timer5_pin_port[1] ^= timer5_pin_mask[1]; } if (timer5_toggle_count > 0) timer5_toggle_count--; } else { TIMSK5 = 0; // disable the interrupt *timer5_pin_port[0] &= ~(timer5_pin_mask[0]); // keep pin low after stop if (timer5_pin_mask[0] != timer5_pin_mask[1]) { *timer5_pin_port[1] &= ~(timer5_pin_mask[1]); // keep pin low after stop } } } #endif