Earle F. Philhower, III
01e9dc99f2
Provide direct connection from BT audio to I2S and PWM audio outputs. Example included showing play/pause operation.
86 lines
2.5 KiB
C++
86 lines
2.5 KiB
C++
/*
|
|
Bluetooth A2DP audio stream consumer - PWMAudio
|
|
|
|
Copyright (c) 2024 Earle F. Philhower, III <earlephilhower@yahoo.com>
|
|
|
|
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
|
|
*/
|
|
|
|
#include "BluetoothAudioConsumerPWM.h"
|
|
#include "A2DPSink.h"
|
|
#include <functional>
|
|
|
|
#define CCALLBACKNAME _BTA2DPPWM
|
|
#include <ctocppcallback.h>
|
|
#define NOPARAMCB(class, cbFcn) \
|
|
(CCALLBACKNAME<void(void), __COUNTER__>::func = std::bind(&class::cbFcn, this), \
|
|
static_cast<void (*)(void)>(CCALLBACKNAME<void(void), __COUNTER__ - 1>::callback))
|
|
|
|
bool BluetoothAudioConsumerPWM::init(uint8_t channels, uint32_t samplerate, A2DPSink *a2dpSink) {
|
|
_channels = channels;
|
|
_samplerate = samplerate;
|
|
_a2dpSink = a2dpSink;
|
|
_pwm->setStereo(channels == 2);
|
|
_pwm->setBuffers(16, 64);
|
|
_pwm->onTransmit(NOPARAMCB(BluetoothAudioConsumerPWM, fill));
|
|
if (_pwm->begin(samplerate)) {
|
|
_state = STATE_INITIALIZED;
|
|
_gain = 64;
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
void BluetoothAudioConsumerPWM::setVolume(uint8_t gain) {
|
|
_gain = gain;
|
|
}
|
|
|
|
void BluetoothAudioConsumerPWM::startStream() {
|
|
if (_state != STATE_INITIALIZED) {
|
|
return;
|
|
}
|
|
_state = STATE_STREAMING;
|
|
}
|
|
|
|
void BluetoothAudioConsumerPWM::stopStream() {
|
|
if (_state != STATE_STREAMING) {
|
|
return;
|
|
}
|
|
_state = STATE_INITIALIZED;
|
|
}
|
|
|
|
void BluetoothAudioConsumerPWM::close() {
|
|
if (_state == STATE_STREAMING) {
|
|
stopStream();
|
|
}
|
|
_state = STATE_OFF;
|
|
_pwm->end();
|
|
}
|
|
|
|
void BluetoothAudioConsumerPWM::fill() {
|
|
int num_samples = _pwm->availableForWrite() / 2;
|
|
int16_t buff[32 * 2];
|
|
while (num_samples > 63) {
|
|
_a2dpSink->playback_handler((int16_t *) buff, 32);
|
|
num_samples -= 64;
|
|
for (int i = 0; i < 64; i++) {
|
|
int32_t tmp = buff[i];
|
|
tmp *= _gain;
|
|
tmp >>= 8;
|
|
_pwm->write((int16_t)tmp);
|
|
}
|
|
}
|
|
}
|