diff options
Diffstat (limited to 'quantum/audio/driver_avr_pwm_hardware.c')
| -rw-r--r-- | quantum/audio/driver_avr_pwm_hardware.c | 322 | 
1 files changed, 322 insertions, 0 deletions
| diff --git a/quantum/audio/driver_avr_pwm_hardware.c b/quantum/audio/driver_avr_pwm_hardware.c new file mode 100644 index 0000000000..492b9bfb04 --- /dev/null +++ b/quantum/audio/driver_avr_pwm_hardware.c @@ -0,0 +1,322 @@ +/* Copyright 2016 Jack Humbert + * Copyright 2020 JohSchneider + * + * This program 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 2 of the License, or + * (at your option) any later version. + * + * This program 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 <http://www.gnu.org/licenses/>. + */ + +#if defined(__AVR__) +#    include <avr/pgmspace.h> +#    include <avr/interrupt.h> +#    include <avr/io.h> +#endif + +#include "audio.h" + +extern bool    playing_note; +extern bool    playing_melody; +extern uint8_t note_timbre; + +#define CPU_PRESCALER 8 + +/* +  Audio Driver: PWM + +  drive up to two speakers through the AVR PWM hardware-peripheral, using timer1 and/or timer3 on Atmega32U4. + +  the primary channel_1 can be connected to either pin PC4 PC5 or PC6 (the later being used by most AVR based keyboards) with a PMW signal generated by timer3 +  and an optional secondary channel_2 on either pin PB5, PB6 or PB7, with a PWM signal from timer1 + +  alternatively, the PWM pins on PORTB can be used as only/primary speaker +*/ + +#if defined(AUDIO_PIN) && (AUDIO_PIN != C4) && (AUDIO_PIN != C5) && (AUDIO_PIN != C6) && (AUDIO_PIN != B5) && (AUDIO_PIN != B6) && (AUDIO_PIN != B7) +#    error "Audio feature enabled, but no suitable pin selected as AUDIO_PIN - see docs/feature_audio under the AVR settings for available options." +#endif + +#if (AUDIO_PIN == C4) || (AUDIO_PIN == C5) || (AUDIO_PIN == C6) +#    define AUDIO1_PIN_SET +#    define AUDIO1_TIMSKx TIMSK3 +#    define AUDIO1_TCCRxA TCCR3A +#    define AUDIO1_TCCRxB TCCR3B +#    define AUDIO1_ICRx ICR3 +#    define AUDIO1_WGMx0 WGM30 +#    define AUDIO1_WGMx1 WGM31 +#    define AUDIO1_WGMx2 WGM32 +#    define AUDIO1_WGMx3 WGM33 +#    define AUDIO1_CSx0 CS30 +#    define AUDIO1_CSx1 CS31 +#    define AUDIO1_CSx2 CS32 + +#    if (AUDIO_PIN == C6) +#        define AUDIO1_COMxy0 COM3A0 +#        define AUDIO1_COMxy1 COM3A1 +#        define AUDIO1_OCIExy OCIE3A +#        define AUDIO1_OCRxy OCR3A +#        define AUDIO1_PIN C6 +#        define AUDIO1_TIMERx_COMPy_vect TIMER3_COMPA_vect +#    elif (AUDIO_PIN == C5) +#        define AUDIO1_COMxy0 COM3B0 +#        define AUDIO1_COMxy1 COM3B1 +#        define AUDIO1_OCIExy OCIE3B +#        define AUDIO1_OCRxy OCR3B +#        define AUDIO1_PIN C5 +#        define AUDIO1_TIMERx_COMPy_vect TIMER3_COMPB_vect +#    elif (AUDIO_PIN == C4) +#        define AUDIO1_COMxy0 COM3C0 +#        define AUDIO1_COMxy1 COM3C1 +#        define AUDIO1_OCIExy OCIE3C +#        define AUDIO1_OCRxy OCR3C +#        define AUDIO1_PIN C4 +#        define AUDIO1_TIMERx_COMPy_vect TIMER3_COMPC_vect +#    endif +#endif + +#if defined(AUDIO_PIN) && defined(AUDIO_PIN_ALT) && (AUDIO_PIN == AUDIO_PIN_ALT) +#    error "Audio feature: AUDIO_PIN and AUDIO_PIN_ALT on the same pin makes no sense." +#endif + +#if ((AUDIO_PIN == B5) && ((AUDIO_PIN_ALT == B6) || (AUDIO_PIN_ALT == B7))) || ((AUDIO_PIN == B6) && ((AUDIO_PIN_ALT == B5) || (AUDIO_PIN_ALT == B7))) || ((AUDIO_PIN == B7) && ((AUDIO_PIN_ALT == B5) || (AUDIO_PIN_ALT == B6))) +#    error "Audio feature: PORTB as AUDIO_PIN and AUDIO_PIN_ALT at the same time is not supported." +#endif + +#if defined(AUDIO_PIN_ALT) && (AUDIO_PIN_ALT != B5) && (AUDIO_PIN_ALT != B6) && (AUDIO_PIN_ALT != B7) +#    error "Audio feature: the pin selected as AUDIO_PIN_ALT is not supported." +#endif + +#if (AUDIO_PIN == B5) || (AUDIO_PIN == B6) || (AUDIO_PIN == B7) || (AUDIO_PIN_ALT == B5) || (AUDIO_PIN_ALT == B6) || (AUDIO_PIN_ALT == B7) +#    define AUDIO2_PIN_SET +#    define AUDIO2_TIMSKx TIMSK1 +#    define AUDIO2_TCCRxA TCCR1A +#    define AUDIO2_TCCRxB TCCR1B +#    define AUDIO2_ICRx ICR1 +#    define AUDIO2_WGMx0 WGM10 +#    define AUDIO2_WGMx1 WGM11 +#    define AUDIO2_WGMx2 WGM12 +#    define AUDIO2_WGMx3 WGM13 +#    define AUDIO2_CSx0 CS10 +#    define AUDIO2_CSx1 CS11 +#    define AUDIO2_CSx2 CS12 + +#    if (AUDIO_PIN == B5) || (AUDIO_PIN_ALT == B5) +#        define AUDIO2_COMxy0 COM1A0 +#        define AUDIO2_COMxy1 COM1A1 +#        define AUDIO2_OCIExy OCIE1A +#        define AUDIO2_OCRxy OCR1A +#        define AUDIO2_PIN B5 +#        define AUDIO2_TIMERx_COMPy_vect TIMER1_COMPA_vect +#    elif (AUDIO_PIN == B6) || (AUDIO_PIN_ALT == B6) +#        define AUDIO2_COMxy0 COM1B0 +#        define AUDIO2_COMxy1 COM1B1 +#        define AUDIO2_OCIExy OCIE1B +#        define AUDIO2_OCRxy OCR1B +#        define AUDIO2_PIN B6 +#        define AUDIO2_TIMERx_COMPy_vect TIMER1_COMPB_vect +#    elif (AUDIO_PIN == B7) || (AUDIO_PIN_ALT == B7) +#        define AUDIO2_COMxy0 COM1C0 +#        define AUDIO2_COMxy1 COM1C1 +#        define AUDIO2_OCIExy OCIE1C +#        define AUDIO2_OCRxy OCR1C +#        define AUDIO2_PIN B7 +#        define AUDIO2_TIMERx_COMPy_vect TIMER1_COMPC_vect +#    endif +#endif + +// C6 seems to be the assumed default by many existing keyboard - but sill warn the user +#if !defined(AUDIO1_PIN_SET) && !defined(AUDIO2_PIN_SET) +#    pragma message "Audio feature enabled, but no suitable pin selected - see docs/feature_audio under the AVR settings for available options. Don't expect to hear anything... :-)" +// TODO: make this an error - go through the breaking-change-process and change all keyboards to the new define +#endif +// ----------------------------------------------------------------------------- + +#ifdef AUDIO1_PIN_SET +static float channel_1_frequency = 0.0f; +void         channel_1_set_frequency(float freq) { +    if (freq == 0.0f)  // a pause/rest is a valid "note" with freq=0 +    { +        // disable the output, but keep the pwm-ISR going (with the previous +        // frequency) so the audio-state keeps getting updated +        // Note: setting the duty-cycle 0 is not possible on non-inverting PWM mode - see the AVR data-sheet +        AUDIO1_TCCRxA &= ~(_BV(AUDIO1_COMxy1) | _BV(AUDIO1_COMxy0)); +        return; +    } else { +        AUDIO1_TCCRxA |= _BV(AUDIO1_COMxy1);  // enable output, PWM mode +    } + +    channel_1_frequency = freq; + +    // set pwm period +    AUDIO1_ICRx = (uint16_t)(((float)F_CPU) / (freq * CPU_PRESCALER)); +    // and duty cycle +    AUDIO1_OCRxy = (uint16_t)((((float)F_CPU) / (freq * CPU_PRESCALER)) * note_timbre / 100); +} + +void channel_1_start(void) { +    // enable timer-counter ISR +    AUDIO1_TIMSKx |= _BV(AUDIO1_OCIExy); +    // enable timer-counter output +    AUDIO1_TCCRxA |= _BV(AUDIO1_COMxy1); +} + +void channel_1_stop(void) { +    // disable timer-counter ISR +    AUDIO1_TIMSKx &= ~_BV(AUDIO1_OCIExy); +    // disable timer-counter output +    AUDIO1_TCCRxA &= ~(_BV(AUDIO1_COMxy1) | _BV(AUDIO1_COMxy0)); +} +#endif + +#ifdef AUDIO2_PIN_SET +static float channel_2_frequency = 0.0f; +void         channel_2_set_frequency(float freq) { +    if (freq == 0.0f) { +        AUDIO2_TCCRxA &= ~(_BV(AUDIO2_COMxy1) | _BV(AUDIO2_COMxy0)); +        return; +    } else { +        AUDIO2_TCCRxA |= _BV(AUDIO2_COMxy1); +    } + +    channel_2_frequency = freq; + +    AUDIO2_ICRx  = (uint16_t)(((float)F_CPU) / (freq * CPU_PRESCALER)); +    AUDIO2_OCRxy = (uint16_t)((((float)F_CPU) / (freq * CPU_PRESCALER)) * note_timbre / 100); +} + +float channel_2_get_frequency(void) { return channel_2_frequency; } + +void channel_2_start(void) { +    AUDIO2_TIMSKx |= _BV(AUDIO2_OCIExy); +    AUDIO2_TCCRxA |= _BV(AUDIO2_COMxy1); +} + +void channel_2_stop(void) { +    AUDIO2_TIMSKx &= ~_BV(AUDIO2_OCIExy); +    AUDIO2_TCCRxA &= ~(_BV(AUDIO2_COMxy1) | _BV(AUDIO2_COMxy0)); +} +#endif + +void audio_driver_initialize() { +#ifdef AUDIO1_PIN_SET +    channel_1_stop(); +    setPinOutput(AUDIO1_PIN); +#endif + +#ifdef AUDIO2_PIN_SET +    channel_2_stop(); +    setPinOutput(AUDIO2_PIN); +#endif + +    // TCCR3A / TCCR3B: Timer/Counter #3 Control Registers TCCR3A/TCCR3B, TCCR1A/TCCR1B +    // Compare Output Mode (COM3An and COM1An) = 0b00 = Normal port operation +    //   OC3A -- PC6 +    //   OC3B -- PC5 +    //   OC3C -- PC4 +    //   OC1A -- PB5 +    //   OC1B -- PB6 +    //   OC1C -- PB7 + +    // Waveform Generation Mode (WGM3n) = 0b1110 = Fast PWM Mode 14. Period = ICR3, Duty Cycle OCR3A) +    //   OCR3A - PC6 +    //   OCR3B - PC5 +    //   OCR3C - PC4 +    //   OCR1A - PB5 +    //   OCR1B - PB6 +    //   OCR1C - PB7 + +    // Clock Select (CS3n) = 0b010 = Clock / 8 +#ifdef AUDIO1_PIN_SET +    // initialize timer-counter +    AUDIO1_TCCRxA = (0 << AUDIO1_COMxy1) | (0 << AUDIO1_COMxy0) | (1 << AUDIO1_WGMx1) | (0 << AUDIO1_WGMx0); +    AUDIO1_TCCRxB = (1 << AUDIO1_WGMx3) | (1 << AUDIO1_WGMx2) | (0 << AUDIO1_CSx2) | (1 << AUDIO1_CSx1) | (0 << AUDIO1_CSx0); +#endif + +#ifdef AUDIO2_PIN_SET +    AUDIO2_TCCRxA = (0 << AUDIO2_COMxy1) | (0 << AUDIO2_COMxy0) | (1 << AUDIO2_WGMx1) | (0 << AUDIO2_WGMx0); +    AUDIO2_TCCRxB = (1 << AUDIO2_WGMx3) | (1 << AUDIO2_WGMx2) | (0 << AUDIO2_CSx2) | (1 << AUDIO2_CSx1) | (0 << AUDIO2_CSx0); +#endif +} + +void audio_driver_stop() { +#ifdef AUDIO1_PIN_SET +    channel_1_stop(); +#endif + +#ifdef AUDIO2_PIN_SET +    channel_2_stop(); +#endif +} + +void audio_driver_start(void) { +#ifdef AUDIO1_PIN_SET +    channel_1_start(); +    if (playing_note) { +        channel_1_set_frequency(audio_get_processed_frequency(0)); +    } +#endif + +#if !defined(AUDIO1_PIN_SET) && defined(AUDIO2_PIN_SET) +    channel_2_start(); +    if (playing_note) { +        channel_2_set_frequency(audio_get_processed_frequency(0)); +    } +#endif +} + +static volatile uint32_t isr_counter = 0; +#ifdef AUDIO1_PIN_SET +ISR(AUDIO1_TIMERx_COMPy_vect) { +    isr_counter++; +    if (isr_counter < channel_1_frequency / (CPU_PRESCALER * 8)) return; + +    isr_counter        = 0; +    bool state_changed = audio_update_state(); + +    if (!playing_note && !playing_melody) { +        channel_1_stop(); +#    ifdef AUDIO2_PIN_SET +        channel_2_stop(); +#    endif +        return; +    } + +    if (state_changed) { +        channel_1_set_frequency(audio_get_processed_frequency(0)); +#    ifdef AUDIO2_PIN_SET +        if (audio_get_number_of_active_tones() > 1) { +            channel_2_set_frequency(audio_get_processed_frequency(1)); +        } else { +            channel_2_stop(); +        } +#    endif +    } +} +#endif + +#if !defined(AUDIO1_PIN_SET) && defined(AUDIO2_PIN_SET) +ISR(AUDIO2_TIMERx_COMPy_vect) { +    isr_counter++; +    if (isr_counter < channel_2_frequency / (CPU_PRESCALER * 8)) return; + +    isr_counter        = 0; +    bool state_changed = audio_update_state(); + +    if (!playing_note && !playing_melody) { +        channel_2_stop(); +        return; +    } + +    if (state_changed) { +        channel_2_set_frequency(audio_get_processed_frequency(0)); +    } +} +#endif | 
