src/gb/audio.c (view raw)
1/* Copyright (c) 2013-2016 Jeffrey Pfau
2 *
3 * This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6#include <mgba/internal/gb/audio.h>
7
8#include <mgba/core/blip_buf.h>
9#include <mgba/core/interface.h>
10#include <mgba/core/sync.h>
11#include <mgba/internal/gb/gb.h>
12#include <mgba/internal/gb/serialize.h>
13#include <mgba/internal/gb/io.h>
14
15#ifdef _3DS
16#define blip_add_delta blip_add_delta_fast
17#endif
18
19#define FRAME_CYCLES (DMG_LR35902_FREQUENCY >> 9)
20
21const uint32_t DMG_LR35902_FREQUENCY = 0x400000;
22static const int CLOCKS_PER_BLIP_FRAME = 0x1000;
23static const unsigned BLIP_BUFFER_SIZE = 0x4000;
24const int GB_AUDIO_VOLUME_MAX = 0x100;
25
26static bool _writeSweep(struct GBAudioSweep* sweep, uint8_t value);
27static void _writeDuty(struct GBAudioEnvelope* envelope, uint8_t value);
28static bool _writeEnvelope(struct GBAudioEnvelope* envelope, uint8_t value);
29
30static void _resetSweep(struct GBAudioSweep* sweep);
31static bool _resetEnvelope(struct GBAudioEnvelope* sweep);
32
33static void _updateEnvelope(struct GBAudioEnvelope* envelope);
34static void _updateEnvelopeDead(struct GBAudioEnvelope* envelope);
35static bool _updateSweep(struct GBAudioSquareChannel* sweep, bool initial);
36
37static void _updateSquareSample(struct GBAudioSquareChannel* ch);
38static int32_t _updateSquareChannel(struct GBAudioSquareChannel* ch);
39
40static void _updateFrame(struct mTiming* timing, void* user, uint32_t cyclesLate);
41static void _updateChannel1(struct mTiming* timing, void* user, uint32_t cyclesLate);
42static void _updateChannel2(struct mTiming* timing, void* user, uint32_t cyclesLate);
43static void _updateChannel3(struct mTiming* timing, void* user, uint32_t cyclesLate);
44static void _fadeChannel3(struct mTiming* timing, void* user, uint32_t cyclesLate);
45static void _updateChannel4(struct mTiming* timing, void* user, uint32_t cyclesLate);
46static void _sample(struct mTiming* timing, void* user, uint32_t cyclesLate);
47
48void GBAudioInit(struct GBAudio* audio, size_t samples, uint8_t* nr52, enum GBAudioStyle style) {
49 audio->samples = samples;
50 audio->left = blip_new(BLIP_BUFFER_SIZE);
51 audio->right = blip_new(BLIP_BUFFER_SIZE);
52 audio->clockRate = DMG_LR35902_FREQUENCY;
53 // Guess too large; we hang producing extra samples if we guess too low
54 blip_set_rates(audio->left, DMG_LR35902_FREQUENCY, 96000);
55 blip_set_rates(audio->right, DMG_LR35902_FREQUENCY, 96000);
56 audio->forceDisableCh[0] = false;
57 audio->forceDisableCh[1] = false;
58 audio->forceDisableCh[2] = false;
59 audio->forceDisableCh[3] = false;
60 audio->masterVolume = GB_AUDIO_VOLUME_MAX;
61 audio->nr52 = nr52;
62 audio->style = style;
63 if (style == GB_AUDIO_GBA) {
64 audio->timingFactor = 4;
65 } else {
66 audio->timingFactor = 1;
67 }
68
69 audio->frameEvent.context = audio;
70 audio->frameEvent.name = "GB Audio Frame Sequencer";
71 audio->frameEvent.callback = _updateFrame;
72 audio->frameEvent.priority = 0x10;
73 audio->ch1Event.context = audio;
74 audio->ch1Event.name = "GB Audio Channel 1";
75 audio->ch1Event.callback = _updateChannel1;
76 audio->ch1Event.priority = 0x11;
77 audio->ch2Event.context = audio;
78 audio->ch2Event.name = "GB Audio Channel 2";
79 audio->ch2Event.callback = _updateChannel2;
80 audio->ch2Event.priority = 0x12;
81 audio->ch3Event.context = audio;
82 audio->ch3Event.name = "GB Audio Channel 3";
83 audio->ch3Event.callback = _updateChannel3;
84 audio->ch3Event.priority = 0x13;
85 audio->ch3Fade.context = audio;
86 audio->ch3Fade.name = "GB Audio Channel 3 Memory";
87 audio->ch3Fade.callback = _fadeChannel3;
88 audio->ch3Fade.priority = 0x14;
89 audio->ch4Event.context = audio;
90 audio->ch4Event.name = "GB Audio Channel 4";
91 audio->ch4Event.callback = _updateChannel4;
92 audio->ch4Event.priority = 0x15;
93 audio->sampleEvent.context = audio;
94 audio->sampleEvent.name = "GB Audio Sample";
95 audio->sampleEvent.callback = _sample;
96 audio->ch1Event.priority = 0x18;
97}
98
99void GBAudioDeinit(struct GBAudio* audio) {
100 blip_delete(audio->left);
101 blip_delete(audio->right);
102}
103
104void GBAudioReset(struct GBAudio* audio) {
105 mTimingDeschedule(audio->timing, &audio->frameEvent);
106 mTimingDeschedule(audio->timing, &audio->ch1Event);
107 mTimingDeschedule(audio->timing, &audio->ch2Event);
108 mTimingDeschedule(audio->timing, &audio->ch3Event);
109 mTimingDeschedule(audio->timing, &audio->ch3Fade);
110 mTimingDeschedule(audio->timing, &audio->ch4Event);
111 mTimingDeschedule(audio->timing, &audio->sampleEvent);
112 mTimingSchedule(audio->timing, &audio->frameEvent, 0);
113 if (audio->style != GB_AUDIO_GBA) {
114 mTimingSchedule(audio->timing, &audio->sampleEvent, 0);
115 }
116 audio->ch1 = (struct GBAudioSquareChannel) { .envelope = { .dead = 2 } };
117 audio->ch2 = (struct GBAudioSquareChannel) { .envelope = { .dead = 2 } };
118 audio->ch3 = (struct GBAudioWaveChannel) { .bank = 0 };
119 // TODO: DMG randomness
120 audio->ch3.wavedata8[0] = 0x00;
121 audio->ch3.wavedata8[1] = 0xFF;
122 audio->ch3.wavedata8[2] = 0x00;
123 audio->ch3.wavedata8[3] = 0xFF;
124 audio->ch3.wavedata8[4] = 0x00;
125 audio->ch3.wavedata8[5] = 0xFF;
126 audio->ch3.wavedata8[6] = 0x00;
127 audio->ch3.wavedata8[7] = 0xFF;
128 audio->ch3.wavedata8[8] = 0x00;
129 audio->ch3.wavedata8[9] = 0xFF;
130 audio->ch3.wavedata8[10] = 0x00;
131 audio->ch3.wavedata8[11] = 0xFF;
132 audio->ch3.wavedata8[12] = 0x00;
133 audio->ch3.wavedata8[13] = 0xFF;
134 audio->ch3.wavedata8[14] = 0x00;
135 audio->ch3.wavedata8[15] = 0xFF;
136 audio->ch4 = (struct GBAudioNoiseChannel) { .envelope = { .dead = 2 } };
137 audio->frame = 0;
138 audio->sampleInterval = 128;
139 audio->lastLeft = 0;
140 audio->lastRight = 0;
141 audio->clock = 0;
142 audio->volumeRight = 0;
143 audio->volumeLeft = 0;
144 audio->ch1Right = false;
145 audio->ch2Right = false;
146 audio->ch3Right = false;
147 audio->ch4Right = false;
148 audio->ch1Left = false;
149 audio->ch2Left = false;
150 audio->ch3Left = false;
151 audio->ch4Left = false;
152 audio->playingCh1 = false;
153 audio->playingCh2 = false;
154 audio->playingCh3 = false;
155 audio->playingCh4 = false;
156}
157
158void GBAudioResizeBuffer(struct GBAudio* audio, size_t samples) {
159 mCoreSyncLockAudio(audio->p->sync);
160 audio->samples = samples;
161 blip_clear(audio->left);
162 blip_clear(audio->right);
163 audio->clock = 0;
164 mCoreSyncConsumeAudio(audio->p->sync);
165}
166
167void GBAudioWriteNR10(struct GBAudio* audio, uint8_t value) {
168 if (!_writeSweep(&audio->ch1.sweep, value)) {
169 mTimingDeschedule(audio->timing, &audio->ch1Event);
170 audio->playingCh1 = false;
171 *audio->nr52 &= ~0x0001;
172 }
173}
174
175void GBAudioWriteNR11(struct GBAudio* audio, uint8_t value) {
176 _writeDuty(&audio->ch1.envelope, value);
177 audio->ch1.control.length = 64 - audio->ch1.envelope.length;
178}
179
180void GBAudioWriteNR12(struct GBAudio* audio, uint8_t value) {
181 if (!_writeEnvelope(&audio->ch1.envelope, value)) {
182 mTimingDeschedule(audio->timing, &audio->ch1Event);
183 audio->playingCh1 = false;
184 *audio->nr52 &= ~0x0001;
185 }
186}
187
188void GBAudioWriteNR13(struct GBAudio* audio, uint8_t value) {
189 audio->ch1.control.frequency &= 0x700;
190 audio->ch1.control.frequency |= GBAudioRegisterControlGetFrequency(value);
191}
192
193void GBAudioWriteNR14(struct GBAudio* audio, uint8_t value) {
194 audio->ch1.control.frequency &= 0xFF;
195 audio->ch1.control.frequency |= GBAudioRegisterControlGetFrequency(value << 8);
196 bool wasStop = audio->ch1.control.stop;
197 audio->ch1.control.stop = GBAudioRegisterControlGetStop(value << 8);
198 if (!wasStop && audio->ch1.control.stop && audio->ch1.control.length && !(audio->frame & 1)) {
199 --audio->ch1.control.length;
200 if (audio->ch1.control.length == 0) {
201 mTimingDeschedule(audio->timing, &audio->ch1Event);
202 audio->playingCh1 = false;
203 }
204 }
205 if (GBAudioRegisterControlIsRestart(value << 8)) {
206 audio->playingCh1 = _resetEnvelope(&audio->ch1.envelope);
207
208 if (audio->playingCh1) {
209 audio->ch1.control.hi = 0;
210 _updateSquareSample(&audio->ch1);
211 }
212
213 audio->ch1.sweep.realFrequency = audio->ch1.control.frequency;
214 _resetSweep(&audio->ch1.sweep);
215 if (audio->playingCh1 && audio->ch1.sweep.shift) {
216 audio->playingCh1 = _updateSweep(&audio->ch1, true);
217 }
218 if (!audio->ch1.control.length) {
219 audio->ch1.control.length = 64;
220 if (audio->ch1.control.stop && !(audio->frame & 1)) {
221 --audio->ch1.control.length;
222 }
223 }
224 mTimingDeschedule(audio->timing, &audio->ch1Event);
225 if (audio->playingCh1 && audio->ch1.envelope.dead != 2) {
226 mTimingSchedule(audio->timing, &audio->ch1Event, 0);
227 }
228 }
229 *audio->nr52 &= ~0x0001;
230 *audio->nr52 |= audio->playingCh1;
231}
232
233void GBAudioWriteNR21(struct GBAudio* audio, uint8_t value) {
234 _writeDuty(&audio->ch2.envelope, value);
235 audio->ch2.control.length = 64 - audio->ch2.envelope.length;
236}
237
238void GBAudioWriteNR22(struct GBAudio* audio, uint8_t value) {
239 if (!_writeEnvelope(&audio->ch2.envelope, value)) {
240 mTimingDeschedule(audio->timing, &audio->ch2Event);
241 audio->playingCh2 = false;
242 *audio->nr52 &= ~0x0002;
243 }
244}
245
246void GBAudioWriteNR23(struct GBAudio* audio, uint8_t value) {
247 audio->ch2.control.frequency &= 0x700;
248 audio->ch2.control.frequency |= GBAudioRegisterControlGetFrequency(value);
249}
250
251void GBAudioWriteNR24(struct GBAudio* audio, uint8_t value) {
252 audio->ch2.control.frequency &= 0xFF;
253 audio->ch2.control.frequency |= GBAudioRegisterControlGetFrequency(value << 8);
254 bool wasStop = audio->ch2.control.stop;
255 audio->ch2.control.stop = GBAudioRegisterControlGetStop(value << 8);
256 if (!wasStop && audio->ch2.control.stop && audio->ch2.control.length && !(audio->frame & 1)) {
257 --audio->ch2.control.length;
258 if (audio->ch2.control.length == 0) {
259 mTimingDeschedule(audio->timing, &audio->ch2Event);
260 audio->playingCh2 = false;
261 }
262 }
263 if (GBAudioRegisterControlIsRestart(value << 8)) {
264 audio->playingCh2 = _resetEnvelope(&audio->ch2.envelope);
265
266 if (audio->playingCh2) {
267 audio->ch2.control.hi = 0;
268 _updateSquareSample(&audio->ch2);
269 }
270
271 if (!audio->ch2.control.length) {
272 audio->ch2.control.length = 64;
273 if (audio->ch2.control.stop && !(audio->frame & 1)) {
274 --audio->ch2.control.length;
275 }
276 }
277 mTimingDeschedule(audio->timing, &audio->ch2Event);
278 if (audio->playingCh2 && audio->ch2.envelope.dead != 2) {
279 mTimingSchedule(audio->timing, &audio->ch2Event, 0);
280 }
281 }
282 *audio->nr52 &= ~0x0002;
283 *audio->nr52 |= audio->playingCh2 << 1;
284}
285
286void GBAudioWriteNR30(struct GBAudio* audio, uint8_t value) {
287 audio->ch3.enable = GBAudioRegisterBankGetEnable(value);
288 if (!audio->ch3.enable) {
289 audio->playingCh3 = false;
290 *audio->nr52 &= ~0x0004;
291 }
292}
293
294void GBAudioWriteNR31(struct GBAudio* audio, uint8_t value) {
295 audio->ch3.length = 256 - value;
296}
297
298void GBAudioWriteNR32(struct GBAudio* audio, uint8_t value) {
299 audio->ch3.volume = GBAudioRegisterBankVolumeGetVolumeGB(value);
300}
301
302void GBAudioWriteNR33(struct GBAudio* audio, uint8_t value) {
303 audio->ch3.rate &= 0x700;
304 audio->ch3.rate |= GBAudioRegisterControlGetRate(value);
305}
306
307void GBAudioWriteNR34(struct GBAudio* audio, uint8_t value) {
308 audio->ch3.rate &= 0xFF;
309 audio->ch3.rate |= GBAudioRegisterControlGetRate(value << 8);
310 bool wasStop = audio->ch3.stop;
311 audio->ch3.stop = GBAudioRegisterControlGetStop(value << 8);
312 if (!wasStop && audio->ch3.stop && audio->ch3.length && !(audio->frame & 1)) {
313 --audio->ch3.length;
314 if (audio->ch3.length == 0) {
315 audio->playingCh3 = false;
316 }
317 }
318 bool wasEnable = audio->playingCh3;
319 if (GBAudioRegisterControlIsRestart(value << 8)) {
320 audio->playingCh3 = audio->ch3.enable;
321 if (!audio->ch3.length) {
322 audio->ch3.length = 256;
323 if (audio->ch3.stop && !(audio->frame & 1)) {
324 --audio->ch3.length;
325 }
326 }
327
328 if (audio->style == GB_AUDIO_DMG && wasEnable && audio->playingCh3 && audio->ch3.readable) {
329 if (audio->ch3.window < 8) {
330 audio->ch3.wavedata8[0] = audio->ch3.wavedata8[audio->ch3.window >> 1];
331 } else {
332 audio->ch3.wavedata8[0] = audio->ch3.wavedata8[((audio->ch3.window >> 1) & ~3)];
333 audio->ch3.wavedata8[1] = audio->ch3.wavedata8[((audio->ch3.window >> 1) & ~3) + 1];
334 audio->ch3.wavedata8[2] = audio->ch3.wavedata8[((audio->ch3.window >> 1) & ~3) + 2];
335 audio->ch3.wavedata8[3] = audio->ch3.wavedata8[((audio->ch3.window >> 1) & ~3) + 3];
336 }
337 }
338 audio->ch3.window = 0;
339 }
340 mTimingDeschedule(audio->timing, &audio->ch3Event);
341 if (audio->playingCh3) {
342 audio->ch3.readable = audio->style != GB_AUDIO_DMG;
343 // TODO: Where does this cycle delay come from?
344 mTimingSchedule(audio->timing, &audio->ch3Event, audio->timingFactor * 4 + 2 * (2048 - audio->ch3.rate));
345 }
346 *audio->nr52 &= ~0x0004;
347 *audio->nr52 |= audio->playingCh3 << 2;
348}
349
350void GBAudioWriteNR41(struct GBAudio* audio, uint8_t value) {
351 _writeDuty(&audio->ch4.envelope, value);
352 audio->ch4.length = 64 - audio->ch4.envelope.length;
353}
354
355void GBAudioWriteNR42(struct GBAudio* audio, uint8_t value) {
356 if (!_writeEnvelope(&audio->ch4.envelope, value)) {
357 mTimingDeschedule(audio->timing, &audio->ch4Event);
358 audio->playingCh4 = false;
359 *audio->nr52 &= ~0x0008;
360 }
361}
362
363void GBAudioWriteNR43(struct GBAudio* audio, uint8_t value) {
364 audio->ch4.ratio = GBAudioRegisterNoiseFeedbackGetRatio(value);
365 audio->ch4.frequency = GBAudioRegisterNoiseFeedbackGetFrequency(value);
366 audio->ch4.power = GBAudioRegisterNoiseFeedbackGetPower(value);
367}
368
369void GBAudioWriteNR44(struct GBAudio* audio, uint8_t value) {
370 bool wasStop = audio->ch4.stop;
371 audio->ch4.stop = GBAudioRegisterNoiseControlGetStop(value);
372 if (!wasStop && audio->ch4.stop && audio->ch4.length && !(audio->frame & 1)) {
373 --audio->ch4.length;
374 if (audio->ch4.length == 0) {
375 mTimingDeschedule(audio->timing, &audio->ch4Event);
376 audio->playingCh4 = false;
377 }
378 }
379 if (GBAudioRegisterNoiseControlIsRestart(value)) {
380 audio->playingCh4 = _resetEnvelope(&audio->ch4.envelope);
381
382 if (audio->ch4.power) {
383 audio->ch4.lfsr = 0x40;
384 } else {
385 audio->ch4.lfsr = 0x4000;
386 }
387 if (!audio->ch4.length) {
388 audio->ch4.length = 64;
389 if (audio->ch4.stop && !(audio->frame & 1)) {
390 --audio->ch4.length;
391 }
392 }
393 mTimingDeschedule(audio->timing, &audio->ch4Event);
394 if (audio->playingCh4 && audio->ch4.envelope.dead != 2) {
395 mTimingSchedule(audio->timing, &audio->ch4Event, 0);
396 }
397 }
398 *audio->nr52 &= ~0x0008;
399 *audio->nr52 |= audio->playingCh4 << 3;
400}
401
402void GBAudioWriteNR50(struct GBAudio* audio, uint8_t value) {
403 audio->volumeRight = GBRegisterNR50GetVolumeRight(value);
404 audio->volumeLeft = GBRegisterNR50GetVolumeLeft(value);
405}
406
407void GBAudioWriteNR51(struct GBAudio* audio, uint8_t value) {
408 audio->ch1Right = GBRegisterNR51GetCh1Right(value);
409 audio->ch2Right = GBRegisterNR51GetCh2Right(value);
410 audio->ch3Right = GBRegisterNR51GetCh3Right(value);
411 audio->ch4Right = GBRegisterNR51GetCh4Right(value);
412 audio->ch1Left = GBRegisterNR51GetCh1Left(value);
413 audio->ch2Left = GBRegisterNR51GetCh2Left(value);
414 audio->ch3Left = GBRegisterNR51GetCh3Left(value);
415 audio->ch4Left = GBRegisterNR51GetCh4Left(value);
416}
417
418void GBAudioWriteNR52(struct GBAudio* audio, uint8_t value) {
419 bool wasEnable = audio->enable;
420 audio->enable = GBAudioEnableGetEnable(value);
421 if (!audio->enable) {
422 audio->playingCh1 = 0;
423 audio->playingCh2 = 0;
424 audio->playingCh3 = 0;
425 audio->playingCh4 = 0;
426 GBAudioWriteNR10(audio, 0);
427 GBAudioWriteNR12(audio, 0);
428 GBAudioWriteNR13(audio, 0);
429 GBAudioWriteNR14(audio, 0);
430 GBAudioWriteNR22(audio, 0);
431 GBAudioWriteNR23(audio, 0);
432 GBAudioWriteNR24(audio, 0);
433 GBAudioWriteNR30(audio, 0);
434 GBAudioWriteNR32(audio, 0);
435 GBAudioWriteNR33(audio, 0);
436 GBAudioWriteNR34(audio, 0);
437 GBAudioWriteNR42(audio, 0);
438 GBAudioWriteNR43(audio, 0);
439 GBAudioWriteNR44(audio, 0);
440 GBAudioWriteNR50(audio, 0);
441 GBAudioWriteNR51(audio, 0);
442 if (audio->style != GB_AUDIO_DMG) {
443 GBAudioWriteNR11(audio, 0);
444 GBAudioWriteNR21(audio, 0);
445 GBAudioWriteNR31(audio, 0);
446 GBAudioWriteNR41(audio, 0);
447 }
448
449 if (audio->p) {
450 audio->p->memory.io[REG_NR10] = 0;
451 audio->p->memory.io[REG_NR11] = 0;
452 audio->p->memory.io[REG_NR12] = 0;
453 audio->p->memory.io[REG_NR13] = 0;
454 audio->p->memory.io[REG_NR14] = 0;
455 audio->p->memory.io[REG_NR21] = 0;
456 audio->p->memory.io[REG_NR22] = 0;
457 audio->p->memory.io[REG_NR23] = 0;
458 audio->p->memory.io[REG_NR24] = 0;
459 audio->p->memory.io[REG_NR30] = 0;
460 audio->p->memory.io[REG_NR31] = 0;
461 audio->p->memory.io[REG_NR32] = 0;
462 audio->p->memory.io[REG_NR33] = 0;
463 audio->p->memory.io[REG_NR34] = 0;
464 audio->p->memory.io[REG_NR42] = 0;
465 audio->p->memory.io[REG_NR43] = 0;
466 audio->p->memory.io[REG_NR44] = 0;
467 audio->p->memory.io[REG_NR50] = 0;
468 audio->p->memory.io[REG_NR51] = 0;
469 if (audio->style != GB_AUDIO_DMG) {
470 audio->p->memory.io[REG_NR11] = 0;
471 audio->p->memory.io[REG_NR21] = 0;
472 audio->p->memory.io[REG_NR31] = 0;
473 audio->p->memory.io[REG_NR41] = 0;
474 }
475 }
476 *audio->nr52 &= ~0x000F;
477 } else if (!wasEnable) {
478 audio->frame = 7;
479 }
480}
481
482void _updateFrame(struct mTiming* timing, void* user, uint32_t cyclesLate) {
483 struct GBAudio* audio = user;
484
485 int frame = (audio->frame + 1) & 7;
486 audio->frame = frame;
487
488 switch (frame) {
489 case 2:
490 case 6:
491 if (audio->ch1.sweep.enable) {
492 --audio->ch1.sweep.step;
493 if (audio->ch1.sweep.step == 0) {
494 audio->playingCh1 = _updateSweep(&audio->ch1, false);
495 *audio->nr52 &= ~0x0001;
496 *audio->nr52 |= audio->playingCh1;
497 }
498 }
499 // Fall through
500 case 0:
501 case 4:
502 if (audio->ch1.control.length && audio->ch1.control.stop) {
503 --audio->ch1.control.length;
504 if (audio->ch1.control.length == 0) {
505 mTimingDeschedule(timing, &audio->ch1Event);
506 audio->playingCh1 = 0;
507 *audio->nr52 &= ~0x0001;
508 }
509 }
510
511 if (audio->ch2.control.length && audio->ch2.control.stop) {
512 --audio->ch2.control.length;
513 if (audio->ch2.control.length == 0) {
514 mTimingDeschedule(timing, &audio->ch2Event);
515 audio->playingCh2 = 0;
516 *audio->nr52 &= ~0x0002;
517 }
518 }
519
520 if (audio->ch3.length && audio->ch3.stop) {
521 --audio->ch3.length;
522 if (audio->ch3.length == 0) {
523 mTimingDeschedule(timing, &audio->ch3Event);
524 audio->playingCh3 = 0;
525 *audio->nr52 &= ~0x0004;
526 }
527 }
528
529 if (audio->ch4.length && audio->ch4.stop) {
530 --audio->ch4.length;
531 if (audio->ch4.length == 0) {
532 mTimingDeschedule(timing, &audio->ch4Event);
533 audio->playingCh4 = 0;
534 *audio->nr52 &= ~0x0008;
535 }
536 }
537 break;
538 case 7:
539 if (audio->playingCh1 && !audio->ch1.envelope.dead) {
540 --audio->ch1.envelope.nextStep;
541 if (audio->ch1.envelope.nextStep == 0) {
542 _updateEnvelope(&audio->ch1.envelope);
543 if (audio->ch1.envelope.dead == 2) {
544 mTimingDeschedule(timing, &audio->ch1Event);
545 }
546 _updateSquareSample(&audio->ch1);
547 }
548 }
549
550 if (audio->playingCh2 && !audio->ch2.envelope.dead) {
551 --audio->ch2.envelope.nextStep;
552 if (audio->ch2.envelope.nextStep == 0) {
553 _updateEnvelope(&audio->ch2.envelope);
554 if (audio->ch2.envelope.dead == 2) {
555 mTimingDeschedule(timing, &audio->ch2Event);
556 }
557 _updateSquareSample(&audio->ch1);
558 }
559 }
560
561 if (audio->playingCh4 && !audio->ch4.envelope.dead) {
562 --audio->ch4.envelope.nextStep;
563 if (audio->ch4.envelope.nextStep == 0) {
564 int8_t sample = (audio->ch4.sample >> 7) * 0x8;
565 _updateEnvelope(&audio->ch4.envelope);
566 if (audio->ch4.envelope.dead == 2) {
567 mTimingDeschedule(timing, &audio->ch4Event);
568 }
569 audio->ch4.sample = sample * audio->ch4.envelope.currentVolume;
570 }
571 }
572 break;
573 }
574
575 mTimingSchedule(timing, &audio->frameEvent, audio->timingFactor * FRAME_CYCLES - cyclesLate);
576}
577
578void GBAudioSamplePSG(struct GBAudio* audio, int16_t* left, int16_t* right) {
579 int sampleLeft = 0;
580 int sampleRight = 0;
581
582 if (audio->playingCh1 && !audio->forceDisableCh[0]) {
583 if (audio->ch1Left) {
584 sampleLeft += audio->ch1.sample;
585 }
586
587 if (audio->ch1Right) {
588 sampleRight += audio->ch1.sample;
589 }
590 }
591
592 if (audio->playingCh2 && !audio->forceDisableCh[1]) {
593 if (audio->ch2Left) {
594 sampleLeft += audio->ch2.sample;
595 }
596
597 if (audio->ch2Right) {
598 sampleRight += audio->ch2.sample;
599 }
600 }
601
602 if (audio->playingCh3 && !audio->forceDisableCh[2]) {
603 if (audio->ch3Left) {
604 sampleLeft += audio->ch3.sample;
605 }
606
607 if (audio->ch3Right) {
608 sampleRight += audio->ch3.sample;
609 }
610 }
611
612 if (audio->playingCh4 && !audio->forceDisableCh[3]) {
613 if (audio->ch4Left) {
614 sampleLeft += audio->ch4.sample;
615 }
616
617 if (audio->ch4Right) {
618 sampleRight += audio->ch4.sample;
619 }
620 }
621
622 *left = sampleLeft * (1 + audio->volumeLeft);
623 *right = sampleRight * (1 + audio->volumeRight);
624}
625
626static void _sample(struct mTiming* timing, void* user, uint32_t cyclesLate) {
627 struct GBAudio* audio = user;
628 int16_t sampleLeft = 0;
629 int16_t sampleRight = 0;
630 GBAudioSamplePSG(audio, &sampleLeft, &sampleRight);
631 sampleLeft = (sampleLeft * audio->masterVolume) >> 6;
632 sampleRight = (sampleRight * audio->masterVolume) >> 6;
633
634 mCoreSyncLockAudio(audio->p->sync);
635 unsigned produced;
636 if ((size_t) blip_samples_avail(audio->left) < audio->samples) {
637 blip_add_delta(audio->left, audio->clock, sampleLeft - audio->lastLeft);
638 blip_add_delta(audio->right, audio->clock, sampleRight - audio->lastRight);
639 audio->lastLeft = sampleLeft;
640 audio->lastRight = sampleRight;
641 audio->clock += audio->sampleInterval;
642 if (audio->clock >= CLOCKS_PER_BLIP_FRAME) {
643 blip_end_frame(audio->left, audio->clock);
644 blip_end_frame(audio->right, audio->clock);
645 audio->clock -= CLOCKS_PER_BLIP_FRAME;
646 }
647 }
648 produced = blip_samples_avail(audio->left);
649 if (audio->p->stream && audio->p->stream->postAudioFrame) {
650 audio->p->stream->postAudioFrame(audio->p->stream, sampleLeft, sampleRight);
651 }
652 bool wait = produced >= audio->samples;
653 mCoreSyncProduceAudio(audio->p->sync, wait);
654
655 if (wait && audio->p->stream && audio->p->stream->postAudioBuffer) {
656 audio->p->stream->postAudioBuffer(audio->p->stream, audio->left, audio->right);
657 }
658 mTimingSchedule(timing, &audio->sampleEvent, audio->sampleInterval * audio->timingFactor - cyclesLate);
659}
660
661bool _resetEnvelope(struct GBAudioEnvelope* envelope) {
662 envelope->currentVolume = envelope->initialVolume;
663 _updateEnvelopeDead(envelope);
664 if (!envelope->dead) {
665 envelope->nextStep = envelope->stepTime;
666 }
667 return envelope->initialVolume || envelope->direction;
668}
669
670void _resetSweep(struct GBAudioSweep* sweep) {
671 sweep->step = sweep->time;
672 sweep->enable = (sweep->step != 8) || sweep->shift;
673 sweep->occurred = false;
674}
675
676bool _writeSweep(struct GBAudioSweep* sweep, uint8_t value) {
677 sweep->shift = GBAudioRegisterSquareSweepGetShift(value);
678 bool oldDirection = sweep->direction;
679 sweep->direction = GBAudioRegisterSquareSweepGetDirection(value);
680 bool on = true;
681 if (sweep->occurred && oldDirection && !sweep->direction) {
682 on = false;
683 }
684 sweep->occurred = false;
685 sweep->time = GBAudioRegisterSquareSweepGetTime(value);
686 if (!sweep->time) {
687 sweep->time = 8;
688 }
689 return on;
690}
691
692void _writeDuty(struct GBAudioEnvelope* envelope, uint8_t value) {
693 envelope->length = GBAudioRegisterDutyGetLength(value);
694 envelope->duty = GBAudioRegisterDutyGetDuty(value);
695}
696
697bool _writeEnvelope(struct GBAudioEnvelope* envelope, uint8_t value) {
698 envelope->stepTime = GBAudioRegisterSweepGetStepTime(value);
699 envelope->direction = GBAudioRegisterSweepGetDirection(value);
700 envelope->initialVolume = GBAudioRegisterSweepGetInitialVolume(value);
701 _updateEnvelopeDead(envelope);
702 envelope->nextStep = envelope->stepTime;
703 return (envelope->initialVolume || envelope->direction) && envelope->dead != 2;
704}
705
706static void _updateSquareSample(struct GBAudioSquareChannel* ch) {
707 ch->sample = (ch->control.hi * ch->envelope.currentVolume - 8) * 0x10;
708}
709
710static int32_t _updateSquareChannel(struct GBAudioSquareChannel* ch) {
711 ch->control.hi = !ch->control.hi;
712 _updateSquareSample(ch);
713 int period = 4 * (2048 - ch->control.frequency);
714 switch (ch->envelope.duty) {
715 case 0:
716 return ch->control.hi ? period : period * 7;
717 case 1:
718 return ch->control.hi ? period * 2 : period * 6;
719 case 2:
720 return period * 4;
721 case 3:
722 return ch->control.hi ? period * 6 : period * 2;
723 default:
724 // This should never be hit
725 return period * 4;
726 }
727}
728
729static void _updateEnvelope(struct GBAudioEnvelope* envelope) {
730 if (envelope->direction) {
731 ++envelope->currentVolume;
732 } else {
733 --envelope->currentVolume;
734 }
735 if (envelope->currentVolume >= 15) {
736 envelope->currentVolume = 15;
737 envelope->dead = 1;
738 } else if (envelope->currentVolume <= 0) {
739 envelope->currentVolume = 0;
740 envelope->dead = 2;
741 } else {
742 envelope->nextStep = envelope->stepTime;
743 }
744}
745
746static void _updateEnvelopeDead(struct GBAudioEnvelope* envelope) {
747 if (!envelope->stepTime) {
748 envelope->dead = envelope->currentVolume ? 1 : 2;
749 } else if (!envelope->direction && !envelope->currentVolume) {
750 envelope->dead = 2;
751 } else if (envelope->direction && envelope->currentVolume == 0xF) {
752 envelope->dead = 1;
753 } else {
754 envelope->dead = 0;
755 }
756}
757
758static bool _updateSweep(struct GBAudioSquareChannel* ch, bool initial) {
759 if (initial || ch->sweep.time != 8) {
760 int frequency = ch->sweep.realFrequency;
761 if (ch->sweep.direction) {
762 frequency -= frequency >> ch->sweep.shift;
763 if (!initial && frequency >= 0) {
764 ch->control.frequency = frequency;
765 ch->sweep.realFrequency = frequency;
766 }
767 } else {
768 frequency += frequency >> ch->sweep.shift;
769 if (frequency < 2048) {
770 if (!initial && ch->sweep.shift) {
771 ch->control.frequency = frequency;
772 ch->sweep.realFrequency = frequency;
773 if (!_updateSweep(ch, true)) {
774 return false;
775 }
776 }
777 } else {
778 return false;
779 }
780 }
781 ch->sweep.occurred = true;
782 }
783 ch->sweep.step = ch->sweep.time;
784 return true;
785}
786
787static void _updateChannel1(struct mTiming* timing, void* user, uint32_t cyclesLate) {
788 struct GBAudio* audio = user;
789 struct GBAudioSquareChannel* ch = &audio->ch1;
790 int cycles = _updateSquareChannel(ch);
791 mTimingSchedule(timing, &audio->ch1Event, audio->timingFactor * cycles - cyclesLate);
792}
793
794static void _updateChannel2(struct mTiming* timing, void* user, uint32_t cyclesLate) {
795 struct GBAudio* audio = user;
796 struct GBAudioSquareChannel* ch = &audio->ch2;
797 int cycles = _updateSquareChannel(ch);
798 mTimingSchedule(timing, &audio->ch2Event, audio->timingFactor * cycles - cyclesLate);
799}
800
801static void _updateChannel3(struct mTiming* timing, void* user, uint32_t cyclesLate) {
802 struct GBAudio* audio = user;
803 struct GBAudioWaveChannel* ch = &audio->ch3;
804 int i;
805 int volume;
806 switch (ch->volume) {
807 case 0:
808 volume = 0;
809 break;
810 case 1:
811 volume = 4;
812 break;
813 case 2:
814 volume = 2;
815 break;
816 case 3:
817 volume = 1;
818 break;
819 default:
820 volume = 3;
821 break;
822 }
823 int start;
824 int end;
825 switch (audio->style) {
826 case GB_AUDIO_DMG:
827 default:
828 ++ch->window;
829 ch->window &= 0x1F;
830 ch->sample = ch->wavedata8[ch->window >> 1];
831 if (!(ch->window & 1)) {
832 ch->sample >>= 4;
833 }
834 ch->sample &= 0xF;
835 break;
836 case GB_AUDIO_GBA:
837 if (ch->size) {
838 start = 7;
839 end = 0;
840 } else if (ch->bank) {
841 start = 7;
842 end = 4;
843 } else {
844 start = 3;
845 end = 0;
846 }
847 uint32_t bitsCarry = ch->wavedata32[end] & 0x000000F0;
848 uint32_t bits;
849 for (i = start; i >= end; --i) {
850 bits = ch->wavedata32[i] & 0x000000F0;
851 ch->wavedata32[i] = ((ch->wavedata32[i] & 0x0F0F0F0F) << 4) | ((ch->wavedata32[i] & 0xF0F0F000) >> 12);
852 ch->wavedata32[i] |= bitsCarry << 20;
853 bitsCarry = bits;
854 }
855 ch->sample = bitsCarry >> 4;
856 break;
857 }
858 ch->sample -= 8;
859 ch->sample *= volume * 4;
860 audio->ch3.readable = true;
861 if (audio->style == GB_AUDIO_DMG) {
862 mTimingSchedule(timing, &audio->ch3Fade, 2 - cyclesLate);
863 }
864 int cycles = 2 * (2048 - ch->rate);
865 mTimingSchedule(timing, &audio->ch3Event, audio->timingFactor * cycles - cyclesLate);
866}
867static void _fadeChannel3(struct mTiming* timing, void* user, uint32_t cyclesLate) {
868 UNUSED(timing);
869 UNUSED(cyclesLate);
870 struct GBAudio* audio = user;
871 audio->ch3.readable = false;
872}
873
874static void _updateChannel4(struct mTiming* timing, void* user, uint32_t cyclesLate) {
875 struct GBAudio* audio = user;
876 struct GBAudioNoiseChannel* ch = &audio->ch4;
877
878 int32_t baseCycles = ch->ratio ? 2 * ch->ratio : 1;
879 baseCycles <<= ch->frequency;
880 baseCycles *= 8 * audio->timingFactor;
881 int32_t cycles = 0;
882
883 do {
884 int lsb = ch->lfsr & 1;
885 ch->sample = lsb * 0x10 - 0x8;
886 ch->sample *= ch->envelope.currentVolume;
887 ch->lfsr >>= 1;
888 ch->lfsr ^= (lsb * 0x60) << (ch->power ? 0 : 8);
889 cycles += baseCycles;
890 } while (cycles < audio->sampleInterval);
891 mTimingSchedule(timing, &audio->ch4Event, cycles - cyclesLate);
892}
893
894void GBAudioPSGSerialize(const struct GBAudio* audio, struct GBSerializedPSGState* state, uint32_t* flagsOut) {
895 uint32_t flags = 0;
896 uint32_t ch1Flags = 0;
897 uint32_t ch2Flags = 0;
898 uint32_t ch4Flags = 0;
899
900 flags = GBSerializedAudioFlagsSetFrame(flags, audio->frame);
901 STORE_32LE(audio->frameEvent.when - mTimingCurrentTime(audio->timing), 0, &state->ch1.nextFrame);
902
903 flags = GBSerializedAudioFlagsSetCh1Volume(flags, audio->ch1.envelope.currentVolume);
904 flags = GBSerializedAudioFlagsSetCh1Dead(flags, audio->ch1.envelope.dead);
905 flags = GBSerializedAudioFlagsSetCh1Hi(flags, audio->ch1.control.hi);
906 flags = GBSerializedAudioFlagsSetCh1SweepEnabled(flags, audio->ch1.sweep.enable);
907 flags = GBSerializedAudioFlagsSetCh1SweepOccurred(flags, audio->ch1.sweep.occurred);
908 ch1Flags = GBSerializedAudioEnvelopeSetLength(ch1Flags, audio->ch1.control.length);
909 ch1Flags = GBSerializedAudioEnvelopeSetNextStep(ch1Flags, audio->ch1.envelope.nextStep);
910 ch1Flags = GBSerializedAudioEnvelopeSetFrequency(ch1Flags, audio->ch1.sweep.realFrequency);
911 STORE_32LE(ch1Flags, 0, &state->ch1.envelope);
912 STORE_32LE(audio->ch1Event.when - mTimingCurrentTime(audio->timing), 0, &state->ch1.nextEvent);
913
914 flags = GBSerializedAudioFlagsSetCh2Volume(flags, audio->ch2.envelope.currentVolume);
915 flags = GBSerializedAudioFlagsSetCh2Dead(flags, audio->ch2.envelope.dead);
916 flags = GBSerializedAudioFlagsSetCh2Hi(flags, audio->ch2.control.hi);
917 ch2Flags = GBSerializedAudioEnvelopeSetLength(ch2Flags, audio->ch2.control.length);
918 ch2Flags = GBSerializedAudioEnvelopeSetNextStep(ch2Flags, audio->ch2.envelope.nextStep);
919 STORE_32LE(ch2Flags, 0, &state->ch2.envelope);
920 STORE_32LE(audio->ch2Event.when - mTimingCurrentTime(audio->timing), 0, &state->ch2.nextEvent);
921
922 flags = GBSerializedAudioFlagsSetCh3Readable(flags, audio->ch3.readable);
923 memcpy(state->ch3.wavebanks, audio->ch3.wavedata32, sizeof(state->ch3.wavebanks));
924 STORE_16LE(audio->ch3.length, 0, &state->ch3.length);
925 STORE_32LE(audio->ch3Event.when - mTimingCurrentTime(audio->timing), 0, &state->ch3.nextEvent);
926 STORE_32LE(audio->ch3Fade.when - mTimingCurrentTime(audio->timing), 0, &state->ch1.nextCh3Fade);
927
928 flags = GBSerializedAudioFlagsSetCh4Volume(flags, audio->ch4.envelope.currentVolume);
929 flags = GBSerializedAudioFlagsSetCh4Dead(flags, audio->ch4.envelope.dead);
930 STORE_32LE(audio->ch4.lfsr, 0, &state->ch4.lfsr);
931 ch4Flags = GBSerializedAudioEnvelopeSetLength(ch4Flags, audio->ch4.length);
932 ch4Flags = GBSerializedAudioEnvelopeSetNextStep(ch4Flags, audio->ch4.envelope.nextStep);
933 STORE_32LE(ch4Flags, 0, &state->ch4.envelope);
934 STORE_32LE(audio->ch4Event.when - mTimingCurrentTime(audio->timing), 0, &state->ch4.nextEvent);
935
936 STORE_32LE(flags, 0, flagsOut);
937}
938
939void GBAudioPSGDeserialize(struct GBAudio* audio, const struct GBSerializedPSGState* state, const uint32_t* flagsIn) {
940 uint32_t flags;
941 uint32_t ch1Flags = 0;
942 uint32_t ch2Flags = 0;
943 uint32_t ch4Flags = 0;
944 uint32_t when;
945
946 audio->playingCh1 = !!(*audio->nr52 & 0x0001);
947 audio->playingCh2 = !!(*audio->nr52 & 0x0002);
948 audio->playingCh3 = !!(*audio->nr52 & 0x0004);
949 audio->playingCh4 = !!(*audio->nr52 & 0x0008);
950 audio->enable = GBAudioEnableGetEnable(*audio->nr52);
951
952 LOAD_32LE(flags, 0, flagsIn);
953 LOAD_32LE(ch1Flags, 0, &state->ch1.envelope);
954 audio->ch1.envelope.currentVolume = GBSerializedAudioFlagsGetCh1Volume(flags);
955 audio->ch1.envelope.dead = GBSerializedAudioFlagsGetCh1Dead(flags);
956 audio->ch1.control.hi = GBSerializedAudioFlagsGetCh1Hi(flags);
957 audio->ch1.sweep.enable = GBSerializedAudioFlagsGetCh1SweepEnabled(flags);
958 audio->ch1.sweep.occurred = GBSerializedAudioFlagsGetCh1SweepOccurred(flags);
959 audio->ch1.control.length = GBSerializedAudioEnvelopeGetLength(ch1Flags);
960 audio->ch1.envelope.nextStep = GBSerializedAudioEnvelopeGetNextStep(ch1Flags);
961 audio->ch1.sweep.realFrequency = GBSerializedAudioEnvelopeGetFrequency(ch1Flags);
962 LOAD_32LE(when, 0, &state->ch1.nextEvent);
963 mTimingDeschedule(audio->timing, &audio->ch1Event);
964 if (audio->ch1.envelope.dead < 2 && audio->playingCh1) {
965 mTimingSchedule(audio->timing, &audio->ch1Event, when);
966 }
967
968 LOAD_32LE(ch2Flags, 0, &state->ch2.envelope);
969 audio->ch2.envelope.currentVolume = GBSerializedAudioFlagsGetCh2Volume(flags);
970 audio->ch2.envelope.dead = GBSerializedAudioFlagsGetCh2Dead(flags);
971 audio->ch2.control.hi = GBSerializedAudioFlagsGetCh2Hi(flags);
972 audio->ch2.control.length = GBSerializedAudioEnvelopeGetLength(ch2Flags);
973 audio->ch2.envelope.nextStep = GBSerializedAudioEnvelopeGetNextStep(ch2Flags);
974 LOAD_32LE(when, 0, &state->ch2.nextEvent);
975 mTimingDeschedule(audio->timing, &audio->ch2Event);
976 if (audio->ch2.envelope.dead < 2 && audio->playingCh2) {
977 mTimingSchedule(audio->timing, &audio->ch2Event, when);
978 }
979
980 audio->ch3.readable = GBSerializedAudioFlagsGetCh3Readable(flags);
981 // TODO: Big endian?
982 memcpy(audio->ch3.wavedata32, state->ch3.wavebanks, sizeof(audio->ch3.wavedata32));
983 LOAD_16LE(audio->ch3.length, 0, &state->ch3.length);
984 LOAD_32LE(when, 0, &state->ch3.nextEvent);
985 mTimingDeschedule(audio->timing, &audio->ch3Event);
986 if (audio->playingCh3) {
987 mTimingSchedule(audio->timing, &audio->ch3Event, when);
988 }
989 LOAD_32LE(when, 0, &state->ch1.nextCh3Fade);
990 if (audio->ch3.readable && audio->style == GB_AUDIO_DMG) {
991 mTimingSchedule(audio->timing, &audio->ch3Fade, when);
992 }
993
994 LOAD_32LE(ch4Flags, 0, &state->ch4.envelope);
995 audio->ch4.envelope.currentVolume = GBSerializedAudioFlagsGetCh4Volume(flags);
996 audio->ch4.envelope.dead = GBSerializedAudioFlagsGetCh4Dead(flags);
997 audio->ch4.length = GBSerializedAudioEnvelopeGetLength(ch4Flags);
998 audio->ch4.envelope.nextStep = GBSerializedAudioEnvelopeGetNextStep(ch4Flags);
999 LOAD_32LE(audio->ch4.lfsr, 0, &state->ch4.lfsr);
1000 LOAD_32LE(when, 0, &state->ch4.nextEvent);
1001 mTimingDeschedule(audio->timing, &audio->ch4Event);
1002 if (audio->ch4.envelope.dead < 2 && audio->playingCh4) {
1003 mTimingSchedule(audio->timing, &audio->ch4Event, when);
1004 }
1005}
1006
1007void GBAudioSerialize(const struct GBAudio* audio, struct GBSerializedState* state) {
1008 GBAudioPSGSerialize(audio, &state->audio.psg, &state->audio.flags);
1009 STORE_32LE(audio->sampleEvent.when - mTimingCurrentTime(audio->timing), 0, &state->audio.nextSample);
1010}
1011
1012void GBAudioDeserialize(struct GBAudio* audio, const struct GBSerializedState* state) {
1013 GBAudioPSGDeserialize(audio, &state->audio.psg, &state->audio.flags);
1014 uint32_t when;
1015 LOAD_32LE(when, 0, &state->audio.nextSample);
1016 mTimingDeschedule(audio->timing, &audio->sampleEvent);
1017 mTimingSchedule(audio->timing, &audio->sampleEvent, when);
1018}