Files
picogus/sw/sbplay.cpp
T

324 lines
9.5 KiB
C++

/*
* Copyright (C) 2022-2024 Ian Scott
*
* 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, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include <stdio.h>
#include <math.h>
#if PICO_ON_DEVICE
#include "hardware/clocks.h"
#include "hardware/structs/clocks.h"
#endif
#include "pico/stdlib.h"
#include "pico/audio_i2s.h"
#include "volctrl.h"
#include "opl.h"
extern "C" void OPL_Pico_simple(int16_t *buffer, uint32_t nsamples);
extern "C" void OPL_Pico_WriteRegister(unsigned int reg_num, unsigned int value);
#include "audio_fifo.h"
#if SOUND_SB
#if SB_BUFFERLESS
extern int16_t sbdsp_sample();
#else // SB_BUFFERLESS
extern uint16_t sbdsp_sample_rate();
extern uint16_t sbdsp_muted();
extern audio_fifo_t* sbdsp_fifo_peek();
#endif // SB_BUFFERLESS
#endif // SOUND_SB
#if defined(SOUND_SB) || defined(USB_MOUSE) || defined(SOUND_MPU)
#include "pico_pic.h"
#endif
#if CDROM
#include "cdrom/cdrom.h"
// extern cdrom_t cdrom;
#endif // CDROM
#include "clamp.h"
#include "cmd_buffers.h"
extern cms_buffer_t opl_buffer;
#ifdef USB_STACK
#include "tusb.h"
#endif
#ifdef USB_MOUSE
#include "mouse/8250uart.h"
#include "mouse/sermouse.h"
#endif
#ifdef SOUND_MPU
#include "flash_settings.h"
extern Settings settings;
#include "mpu401/export.h"
#endif
extern uint LED_PIN;
#if PICO_ON_DEVICE
#include "pico/binary_info.h"
bi_decl(bi_3pins_with_names(PICO_AUDIO_I2S_DATA_PIN, "I2S DIN", PICO_AUDIO_I2S_CLOCK_PIN_BASE, "I2S BCK", PICO_AUDIO_I2S_CLOCK_PIN_BASE+1, "I2S LRCK"));
#endif
/*
Minimum expected aample rate from DSP should be 8000hz?
Maximum number of DSP to process at once should be 64.
49716 / 8000 = 6.2145 * 64 = 397
*/
#define SAMPLES_PER_BUFFER 256
struct audio_buffer_pool *init_audio() {
static audio_format_t audio_format = {
//.sample_freq = 49716,
.sample_freq = 44100,
.format = AUDIO_BUFFER_FORMAT_PCM_S16,
.channel_count = 2,
};
static struct audio_buffer_format producer_format = {
.format = &audio_format,
.sample_stride = 4
};
struct audio_buffer_pool *producer_pool = audio_new_producer_pool(&producer_format, 2,
SAMPLES_PER_BUFFER); // todo correct size
bool __unused ok;
const struct audio_format *output_format;
struct audio_i2s_config config = {
.data_pin = PICO_AUDIO_I2S_DATA_PIN,
.clock_pin_base = PICO_AUDIO_I2S_CLOCK_PIN_BASE,
.dma_channel = 6,
.pio_sm = 3,
};
output_format = audio_i2s_setup(&audio_format, &config);
if (!output_format) {
panic("PicoAudio: Unable to open audio device.\n");
}
//ok = audio_i2s_connect(producer_pool);
ok = audio_i2s_connect_extra(producer_pool, false, 0, 0, NULL);
assert(ok);
audio_i2s_set_enabled(true);
return producer_pool;
}
/* Fixed-point format: Q16.16 (16 bits integer, 16 bits fractional) */
static constexpr uint32_t FRAC_BITS = 16;
static constexpr uint32_t FRAC_MASK = (1u << FRAC_BITS) - 1;
static inline uint32_t fixed_ratio(uint16_t a, uint16_t b) {
return ((uint32_t)a << FRAC_BITS) / b;
}
/**
* Linear interpolation in fixed-point
* v0 and v1 are sample values, frac is the fractional position
*/
static inline int16_t lerp_fixed(int16_t v0, int16_t v1, uint32_t frac) {
return v0 + (int16_t)(((int32_t)(v1 - v0) * frac) >> FRAC_BITS);
}
void play_adlib() {
puts("starting core 1");
// flash_safe_execute_core_init();
uint32_t start, end;
set_volume(CMD_OPLVOL);
#if defined(SOUND_SB) || defined(USB_MOUSE) || defined(SOUND_MPU)
// Init PIC on this core so it handles timers
PIC_Init();
#endif
#ifdef USB_STACK
// Init TinyUSB for joystick support
tuh_init(BOARD_TUH_RHPORT);
#endif
clamp_setup();
#ifdef SOUND_MPU
MPU401_Init(settings.MPU.delaySysex, settings.MPU.fakeAllNotesOff);
#endif
struct audio_buffer_pool *ap = init_audio();
#if SOUND_SB && !SB_BUFFERLESS
// uint8_t sb_samples[512] = {128};
audio_fifo_t* sb_fifo = sbdsp_fifo_peek();
#endif
#ifdef CDROM
int16_t cd_samples[SAMPLES_PER_BUFFER * 2];
bool has_cd_samples;
#endif
#ifdef SOUND_SB
// int16_t sb_sample = 0;
uint32_t sb_ratio = 0;
uint32_t sb_pos = 0;
uint32_t sb_index_old = 0xffffffff;
uint32_t sb_index = 0;
uint32_t sb_frac = 0;
// uint32_t sb_sample_idx = 0x0;
uint32_t sb_left = 0;
set_volume(CMD_SBVOL);
#endif
uint32_t cd_left = 0;
uint32_t cd_index = 0;
constexpr uint32_t OPL_SAMPLE_COUNT = 8;
constexpr uint32_t OPL_BUFFER_BITS = (OPL_SAMPLE_COUNT << 1) - 1;
int16_t opl_samples[OPL_SAMPLE_COUNT << 1] = {0};
uint32_t opl_ratio = fixed_ratio(49716, 44100);
printf("opl_ratio: %x ", opl_ratio);
uint32_t opl_pos = 0;
uint32_t opl_index = 0;
uint32_t opl_sample_idx = 0x0;
// int16_t cd_samples[1024] = {0};
int32_t accum[2] = {0};
for (;;) {
#if CDROM
has_cd_samples = cdrom_audio_callback_simple(&cdrom, cd_samples, SAMPLES_PER_BUFFER << 1, true);
#endif
struct audio_buffer *buffer = take_audio_buffer(ap, true);
int16_t *samples = (int16_t *) buffer->buffer->bytes;
// Do mixing with lerp
//
#if !SB_BUFFERLESS
for (int i = 0; i < SAMPLES_PER_BUFFER; ++i) {
#endif // !SB_BUFFERLESS
accum[0] = accum[1] = 0;
#if CDROM
if (has_cd_samples) {
accum[0] += cd_samples[i << 1];
accum[1] += cd_samples[(i << 1) + 1];
}
#endif // CDROM
uint32_t opl_index = (opl_pos >> FRAC_BITS);
// uint32_t opl_index = i;
uint32_t opl_frac = opl_pos & FRAC_MASK;
opl_pos += opl_ratio;
#if !SB_BUFFERLESS // don't support OPL in bufferless for now
if (
((opl_index & OPL_SAMPLE_COUNT) && opl_sample_idx != 0x0) ||
(!(opl_index & OPL_SAMPLE_COUNT) && opl_sample_idx != OPL_SAMPLE_COUNT)
) {
opl_sample_idx = (opl_index + OPL_SAMPLE_COUNT) & OPL_SAMPLE_COUNT;
// bool notfirst = false;
while (opl_buffer.tail != opl_buffer.head) {
// if (!notfirst) {
#ifndef PICOW
// gpio_xor_mask(LED_PIN);
#endif
// notfirst = true;
// }
auto cmd = opl_buffer.cmds[opl_buffer.tail];
OPL_Pico_WriteRegister(cmd.addr, cmd.data);
++opl_buffer.tail;
}
OPL_Pico_simple(opl_samples + opl_sample_idx, OPL_SAMPLE_COUNT);
}
int32_t opl_sample = lerp_fixed(
opl_samples[opl_index & OPL_BUFFER_BITS],
opl_samples[(opl_index + 1) & OPL_BUFFER_BITS],
opl_frac);
opl_sample = scale_sample(opl_sample << 2, opl_volume, 1);
accum[0] += opl_sample;
accum[1] += opl_sample;
#if SOUND_SB
if (!sb_left) {
// putchar('t');
uint32_t num_samples = 256;
sb_left = fifo_take_samples(sb_fifo, num_samples);
}
if (sb_left) {
sb_index = (sb_pos >> FRAC_BITS);
if (sb_index_old != sb_index) {
sb_left--;
}
sb_index_old = sb_index;
sb_frac = sb_pos & FRAC_MASK;
//sb_ratio = fixed_ratio(sbdsp_sample_rate(), 44100);
static uint16_t last_sb_rate = 0;
uint16_t current_rate = sbdsp_sample_rate();
if (current_rate != last_sb_rate)
{
sb_ratio = fixed_ratio(current_rate, 44100);
last_sb_rate = current_rate;
}
sb_pos += sb_ratio;
// putchar('p');
if (!sbdsp_muted()) {
//int16_t sb_sample = sb_fifo->buffer[sb_index & AUDIO_FIFO_BITS];
int16_t *fifo_buf = sb_fifo->buffer;
int16_t sb_sample = fifo_buf[sb_index & AUDIO_FIFO_BITS];
sb_sample = scale_sample((int32_t)sb_sample >> 1, sb_volume, 1);
accum[0] += sb_sample;
accum[1] += sb_sample;
}
}
#endif // SOUND_SB
samples[i << 1] = clamp16(accum[0]);
samples[(i << 1) + 1] = clamp16(accum[1]);
}
buffer->sample_count = SAMPLES_PER_BUFFER;
#else // !SB_BUFFERLESS
samples[0] = clamp16(accum[0]);
samples[1] = clamp16(accum[1]);
buffer->sample_count = 1;
#endif // !SB_BUFFERLESS
give_audio_buffer(ap, buffer);
#ifdef USB_STACK
// Service TinyUSB events
tuh_task();
#endif
#ifdef USB_MOUSE
// mouse task
sermouse_core1_task();
// uart emulation task
uartemu_core1_task();
#endif
#ifdef SOUND_MPU
send_midi_bytes(8);
#endif
#ifdef CDROM
cdrom_tasks(&cdrom);
#endif
}
}