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->ch3Fade);
341 mTimingDeschedule(audio->timing, &audio->ch3Event);
342 if (audio->playingCh3) {
343 audio->ch3.readable = audio->style != GB_AUDIO_DMG;
344 // TODO: Where does this cycle delay come from?
345 mTimingSchedule(audio->timing, &audio->ch3Event, audio->timingFactor * 4 + 2 * (2048 - audio->ch3.rate));
346 }
347 *audio->nr52 &= ~0x0004;
348 *audio->nr52 |= audio->playingCh3 << 2;
349}
350
351void GBAudioWriteNR41(struct GBAudio* audio, uint8_t value) {
352 _writeDuty(&audio->ch4.envelope, value);
353 audio->ch4.length = 64 - audio->ch4.envelope.length;
354}
355
356void GBAudioWriteNR42(struct GBAudio* audio, uint8_t value) {
357 if (!_writeEnvelope(&audio->ch4.envelope, value)) {
358 mTimingDeschedule(audio->timing, &audio->ch4Event);
359 audio->playingCh4 = false;
360 *audio->nr52 &= ~0x0008;
361 }
362}
363
364void GBAudioWriteNR43(struct GBAudio* audio, uint8_t value) {
365 audio->ch4.ratio = GBAudioRegisterNoiseFeedbackGetRatio(value);
366 audio->ch4.frequency = GBAudioRegisterNoiseFeedbackGetFrequency(value);
367 audio->ch4.power = GBAudioRegisterNoiseFeedbackGetPower(value);
368}
369
370void GBAudioWriteNR44(struct GBAudio* audio, uint8_t value) {
371 bool wasStop = audio->ch4.stop;
372 audio->ch4.stop = GBAudioRegisterNoiseControlGetStop(value);
373 if (!wasStop && audio->ch4.stop && audio->ch4.length && !(audio->frame & 1)) {
374 --audio->ch4.length;
375 if (audio->ch4.length == 0) {
376 mTimingDeschedule(audio->timing, &audio->ch4Event);
377 audio->playingCh4 = false;
378 }
379 }
380 if (GBAudioRegisterNoiseControlIsRestart(value)) {
381 audio->playingCh4 = _resetEnvelope(&audio->ch4.envelope);
382
383 if (audio->ch4.power) {
384 audio->ch4.lfsr = 0x40;
385 } else {
386 audio->ch4.lfsr = 0x4000;
387 }
388 if (!audio->ch4.length) {
389 audio->ch4.length = 64;
390 if (audio->ch4.stop && !(audio->frame & 1)) {
391 --audio->ch4.length;
392 }
393 }
394 mTimingDeschedule(audio->timing, &audio->ch4Event);
395 if (audio->playingCh4 && audio->ch4.envelope.dead != 2) {
396 mTimingSchedule(audio->timing, &audio->ch4Event, 0);
397 }
398 }
399 *audio->nr52 &= ~0x0008;
400 *audio->nr52 |= audio->playingCh4 << 3;
401}
402
403void GBAudioWriteNR50(struct GBAudio* audio, uint8_t value) {
404 audio->volumeRight = GBRegisterNR50GetVolumeRight(value);
405 audio->volumeLeft = GBRegisterNR50GetVolumeLeft(value);
406}
407
408void GBAudioWriteNR51(struct GBAudio* audio, uint8_t value) {
409 audio->ch1Right = GBRegisterNR51GetCh1Right(value);
410 audio->ch2Right = GBRegisterNR51GetCh2Right(value);
411 audio->ch3Right = GBRegisterNR51GetCh3Right(value);
412 audio->ch4Right = GBRegisterNR51GetCh4Right(value);
413 audio->ch1Left = GBRegisterNR51GetCh1Left(value);
414 audio->ch2Left = GBRegisterNR51GetCh2Left(value);
415 audio->ch3Left = GBRegisterNR51GetCh3Left(value);
416 audio->ch4Left = GBRegisterNR51GetCh4Left(value);
417}
418
419void GBAudioWriteNR52(struct GBAudio* audio, uint8_t value) {
420 bool wasEnable = audio->enable;
421 audio->enable = GBAudioEnableGetEnable(value);
422 if (!audio->enable) {
423 audio->playingCh1 = 0;
424 audio->playingCh2 = 0;
425 audio->playingCh3 = 0;
426 audio->playingCh4 = 0;
427 GBAudioWriteNR10(audio, 0);
428 GBAudioWriteNR12(audio, 0);
429 GBAudioWriteNR13(audio, 0);
430 GBAudioWriteNR14(audio, 0);
431 GBAudioWriteNR22(audio, 0);
432 GBAudioWriteNR23(audio, 0);
433 GBAudioWriteNR24(audio, 0);
434 GBAudioWriteNR30(audio, 0);
435 GBAudioWriteNR32(audio, 0);
436 GBAudioWriteNR33(audio, 0);
437 GBAudioWriteNR34(audio, 0);
438 GBAudioWriteNR42(audio, 0);
439 GBAudioWriteNR43(audio, 0);
440 GBAudioWriteNR44(audio, 0);
441 GBAudioWriteNR50(audio, 0);
442 GBAudioWriteNR51(audio, 0);
443 if (audio->style != GB_AUDIO_DMG) {
444 GBAudioWriteNR11(audio, 0);
445 GBAudioWriteNR21(audio, 0);
446 GBAudioWriteNR31(audio, 0);
447 GBAudioWriteNR41(audio, 0);
448 }
449
450 if (audio->p) {
451 audio->p->memory.io[REG_NR10] = 0;
452 audio->p->memory.io[REG_NR11] = 0;
453 audio->p->memory.io[REG_NR12] = 0;
454 audio->p->memory.io[REG_NR13] = 0;
455 audio->p->memory.io[REG_NR14] = 0;
456 audio->p->memory.io[REG_NR21] = 0;
457 audio->p->memory.io[REG_NR22] = 0;
458 audio->p->memory.io[REG_NR23] = 0;
459 audio->p->memory.io[REG_NR24] = 0;
460 audio->p->memory.io[REG_NR30] = 0;
461 audio->p->memory.io[REG_NR31] = 0;
462 audio->p->memory.io[REG_NR32] = 0;
463 audio->p->memory.io[REG_NR33] = 0;
464 audio->p->memory.io[REG_NR34] = 0;
465 audio->p->memory.io[REG_NR42] = 0;
466 audio->p->memory.io[REG_NR43] = 0;
467 audio->p->memory.io[REG_NR44] = 0;
468 audio->p->memory.io[REG_NR50] = 0;
469 audio->p->memory.io[REG_NR51] = 0;
470 if (audio->style != GB_AUDIO_DMG) {
471 audio->p->memory.io[REG_NR11] = 0;
472 audio->p->memory.io[REG_NR21] = 0;
473 audio->p->memory.io[REG_NR31] = 0;
474 audio->p->memory.io[REG_NR41] = 0;
475 }
476 }
477 *audio->nr52 &= ~0x000F;
478 } else if (!wasEnable) {
479 audio->frame = 7;
480 }
481}
482
483void _updateFrame(struct mTiming* timing, void* user, uint32_t cyclesLate) {
484 struct GBAudio* audio = user;
485
486 int frame = (audio->frame + 1) & 7;
487 audio->frame = frame;
488
489 switch (frame) {
490 case 2:
491 case 6:
492 if (audio->ch1.sweep.enable) {
493 --audio->ch1.sweep.step;
494 if (audio->ch1.sweep.step == 0) {
495 audio->playingCh1 = _updateSweep(&audio->ch1, false);
496 *audio->nr52 &= ~0x0001;
497 *audio->nr52 |= audio->playingCh1;
498 }
499 }
500 // Fall through
501 case 0:
502 case 4:
503 if (audio->ch1.control.length && audio->ch1.control.stop) {
504 --audio->ch1.control.length;
505 if (audio->ch1.control.length == 0) {
506 mTimingDeschedule(timing, &audio->ch1Event);
507 audio->playingCh1 = 0;
508 *audio->nr52 &= ~0x0001;
509 }
510 }
511
512 if (audio->ch2.control.length && audio->ch2.control.stop) {
513 --audio->ch2.control.length;
514 if (audio->ch2.control.length == 0) {
515 mTimingDeschedule(timing, &audio->ch2Event);
516 audio->playingCh2 = 0;
517 *audio->nr52 &= ~0x0002;
518 }
519 }
520
521 if (audio->ch3.length && audio->ch3.stop) {
522 --audio->ch3.length;
523 if (audio->ch3.length == 0) {
524 mTimingDeschedule(timing, &audio->ch3Event);
525 audio->playingCh3 = 0;
526 *audio->nr52 &= ~0x0004;
527 }
528 }
529
530 if (audio->ch4.length && audio->ch4.stop) {
531 --audio->ch4.length;
532 if (audio->ch4.length == 0) {
533 mTimingDeschedule(timing, &audio->ch4Event);
534 audio->playingCh4 = 0;
535 *audio->nr52 &= ~0x0008;
536 }
537 }
538 break;
539 case 7:
540 if (audio->playingCh1 && !audio->ch1.envelope.dead) {
541 --audio->ch1.envelope.nextStep;
542 if (audio->ch1.envelope.nextStep == 0) {
543 _updateEnvelope(&audio->ch1.envelope);
544 if (audio->ch1.envelope.dead == 2) {
545 mTimingDeschedule(timing, &audio->ch1Event);
546 }
547 _updateSquareSample(&audio->ch1);
548 }
549 }
550
551 if (audio->playingCh2 && !audio->ch2.envelope.dead) {
552 --audio->ch2.envelope.nextStep;
553 if (audio->ch2.envelope.nextStep == 0) {
554 _updateEnvelope(&audio->ch2.envelope);
555 if (audio->ch2.envelope.dead == 2) {
556 mTimingDeschedule(timing, &audio->ch2Event);
557 }
558 _updateSquareSample(&audio->ch2);
559 }
560 }
561
562 if (audio->playingCh4 && !audio->ch4.envelope.dead) {
563 --audio->ch4.envelope.nextStep;
564 if (audio->ch4.envelope.nextStep == 0) {
565 int8_t sample = (audio->ch4.sample >> 7) * 0x8;
566 _updateEnvelope(&audio->ch4.envelope);
567 if (audio->ch4.envelope.dead == 2) {
568 mTimingDeschedule(timing, &audio->ch4Event);
569 }
570 audio->ch4.sample = sample * audio->ch4.envelope.currentVolume;
571 }
572 }
573 break;
574 }
575
576 mTimingSchedule(timing, &audio->frameEvent, audio->timingFactor * FRAME_CYCLES - cyclesLate);
577}
578
579void GBAudioSamplePSG(struct GBAudio* audio, int16_t* left, int16_t* right) {
580 int sampleLeft = 0;
581 int sampleRight = 0;
582
583 if (audio->playingCh1 && !audio->forceDisableCh[0]) {
584 if (audio->ch1Left) {
585 sampleLeft += audio->ch1.sample;
586 }
587
588 if (audio->ch1Right) {
589 sampleRight += audio->ch1.sample;
590 }
591 }
592
593 if (audio->playingCh2 && !audio->forceDisableCh[1]) {
594 if (audio->ch2Left) {
595 sampleLeft += audio->ch2.sample;
596 }
597
598 if (audio->ch2Right) {
599 sampleRight += audio->ch2.sample;
600 }
601 }
602
603 if (audio->playingCh3 && !audio->forceDisableCh[2]) {
604 if (audio->ch3Left) {
605 sampleLeft += audio->ch3.sample;
606 }
607
608 if (audio->ch3Right) {
609 sampleRight += audio->ch3.sample;
610 }
611 }
612
613 if (audio->playingCh4 && !audio->forceDisableCh[3]) {
614 if (audio->ch4Left) {
615 sampleLeft += audio->ch4.sample;
616 }
617
618 if (audio->ch4Right) {
619 sampleRight += audio->ch4.sample;
620 }
621 }
622
623 int dcOffset = audio->style == GB_AUDIO_GBA ? 0 : 0x1FC;
624 *left = (sampleLeft - dcOffset) * (1 + audio->volumeLeft);
625 *right = (sampleRight - dcOffset) * (1 + audio->volumeRight);
626}
627
628static void _sample(struct mTiming* timing, void* user, uint32_t cyclesLate) {
629 struct GBAudio* audio = user;
630 int16_t sampleLeft = 0;
631 int16_t sampleRight = 0;
632 GBAudioSamplePSG(audio, &sampleLeft, &sampleRight);
633 sampleLeft = (sampleLeft * audio->masterVolume) >> 6;
634 sampleRight = (sampleRight * audio->masterVolume) >> 6;
635
636 mCoreSyncLockAudio(audio->p->sync);
637 unsigned produced;
638 if ((size_t) blip_samples_avail(audio->left) < audio->samples) {
639 blip_add_delta(audio->left, audio->clock, sampleLeft - audio->lastLeft);
640 blip_add_delta(audio->right, audio->clock, sampleRight - audio->lastRight);
641 audio->lastLeft = sampleLeft;
642 audio->lastRight = sampleRight;
643 audio->clock += audio->sampleInterval;
644 if (audio->clock >= CLOCKS_PER_BLIP_FRAME) {
645 blip_end_frame(audio->left, CLOCKS_PER_BLIP_FRAME);
646 blip_end_frame(audio->right, CLOCKS_PER_BLIP_FRAME);
647 audio->clock -= CLOCKS_PER_BLIP_FRAME;
648 }
649 }
650 produced = blip_samples_avail(audio->left);
651 if (audio->p->stream && audio->p->stream->postAudioFrame) {
652 audio->p->stream->postAudioFrame(audio->p->stream, sampleLeft, sampleRight);
653 }
654 bool wait = produced >= audio->samples;
655 mCoreSyncProduceAudio(audio->p->sync, wait);
656
657 if (wait && audio->p->stream && audio->p->stream->postAudioBuffer) {
658 audio->p->stream->postAudioBuffer(audio->p->stream, audio->left, audio->right);
659 }
660 mTimingSchedule(timing, &audio->sampleEvent, audio->sampleInterval * audio->timingFactor - cyclesLate);
661}
662
663bool _resetEnvelope(struct GBAudioEnvelope* envelope) {
664 envelope->currentVolume = envelope->initialVolume;
665 _updateEnvelopeDead(envelope);
666 if (!envelope->dead) {
667 envelope->nextStep = envelope->stepTime;
668 }
669 return envelope->initialVolume || envelope->direction;
670}
671
672void _resetSweep(struct GBAudioSweep* sweep) {
673 sweep->step = sweep->time;
674 sweep->enable = (sweep->step != 8) || sweep->shift;
675 sweep->occurred = false;
676}
677
678bool _writeSweep(struct GBAudioSweep* sweep, uint8_t value) {
679 sweep->shift = GBAudioRegisterSquareSweepGetShift(value);
680 bool oldDirection = sweep->direction;
681 sweep->direction = GBAudioRegisterSquareSweepGetDirection(value);
682 bool on = true;
683 if (sweep->occurred && oldDirection && !sweep->direction) {
684 on = false;
685 }
686 sweep->occurred = false;
687 sweep->time = GBAudioRegisterSquareSweepGetTime(value);
688 if (!sweep->time) {
689 sweep->time = 8;
690 }
691 return on;
692}
693
694void _writeDuty(struct GBAudioEnvelope* envelope, uint8_t value) {
695 envelope->length = GBAudioRegisterDutyGetLength(value);
696 envelope->duty = GBAudioRegisterDutyGetDuty(value);
697}
698
699bool _writeEnvelope(struct GBAudioEnvelope* envelope, uint8_t value) {
700 envelope->stepTime = GBAudioRegisterSweepGetStepTime(value);
701 envelope->direction = GBAudioRegisterSweepGetDirection(value);
702 envelope->initialVolume = GBAudioRegisterSweepGetInitialVolume(value);
703 if (!envelope->stepTime) {
704 // TODO: Improve "zombie" mode
705 ++envelope->currentVolume;
706 envelope->currentVolume &= 0xF;
707 }
708 _updateEnvelopeDead(envelope);
709 envelope->nextStep = envelope->stepTime;
710 return (envelope->initialVolume || envelope->direction) && envelope->dead != 2;
711}
712
713static void _updateSquareSample(struct GBAudioSquareChannel* ch) {
714 ch->sample = ch->control.hi * ch->envelope.currentVolume * 0x8;
715}
716
717static int32_t _updateSquareChannel(struct GBAudioSquareChannel* ch) {
718 ch->control.hi = !ch->control.hi;
719 _updateSquareSample(ch);
720 int period = 4 * (2048 - ch->control.frequency);
721 switch (ch->envelope.duty) {
722 case 0:
723 return ch->control.hi ? period : period * 7;
724 case 1:
725 return ch->control.hi ? period * 2 : period * 6;
726 case 2:
727 return period * 4;
728 case 3:
729 return ch->control.hi ? period * 6 : period * 2;
730 default:
731 // This should never be hit
732 return period * 4;
733 }
734}
735
736static void _updateEnvelope(struct GBAudioEnvelope* envelope) {
737 if (envelope->direction) {
738 ++envelope->currentVolume;
739 } else {
740 --envelope->currentVolume;
741 }
742 if (envelope->currentVolume >= 15) {
743 envelope->currentVolume = 15;
744 envelope->dead = 1;
745 } else if (envelope->currentVolume <= 0) {
746 envelope->currentVolume = 0;
747 envelope->dead = 2;
748 } else {
749 envelope->nextStep = envelope->stepTime;
750 }
751}
752
753static void _updateEnvelopeDead(struct GBAudioEnvelope* envelope) {
754 if (!envelope->stepTime) {
755 envelope->dead = envelope->currentVolume ? 1 : 2;
756 } else if (!envelope->direction && !envelope->currentVolume) {
757 envelope->dead = 2;
758 } else if (envelope->direction && envelope->currentVolume == 0xF) {
759 envelope->dead = 1;
760 } else {
761 envelope->dead = 0;
762 }
763}
764
765static bool _updateSweep(struct GBAudioSquareChannel* ch, bool initial) {
766 if (initial || ch->sweep.time != 8) {
767 int frequency = ch->sweep.realFrequency;
768 if (ch->sweep.direction) {
769 frequency -= frequency >> ch->sweep.shift;
770 if (!initial && frequency >= 0) {
771 ch->control.frequency = frequency;
772 ch->sweep.realFrequency = frequency;
773 }
774 } else {
775 frequency += frequency >> ch->sweep.shift;
776 if (frequency < 2048) {
777 if (!initial && ch->sweep.shift) {
778 ch->control.frequency = frequency;
779 ch->sweep.realFrequency = frequency;
780 if (!_updateSweep(ch, true)) {
781 return false;
782 }
783 }
784 } else {
785 return false;
786 }
787 }
788 ch->sweep.occurred = true;
789 }
790 ch->sweep.step = ch->sweep.time;
791 return true;
792}
793
794static void _updateChannel1(struct mTiming* timing, void* user, uint32_t cyclesLate) {
795 struct GBAudio* audio = user;
796 struct GBAudioSquareChannel* ch = &audio->ch1;
797 int cycles = _updateSquareChannel(ch);
798 mTimingSchedule(timing, &audio->ch1Event, audio->timingFactor * cycles - cyclesLate);
799}
800
801static void _updateChannel2(struct mTiming* timing, void* user, uint32_t cyclesLate) {
802 struct GBAudio* audio = user;
803 struct GBAudioSquareChannel* ch = &audio->ch2;
804 int cycles = _updateSquareChannel(ch);
805 mTimingSchedule(timing, &audio->ch2Event, audio->timingFactor * cycles - cyclesLate);
806}
807
808static void _updateChannel3(struct mTiming* timing, void* user, uint32_t cyclesLate) {
809 struct GBAudio* audio = user;
810 struct GBAudioWaveChannel* ch = &audio->ch3;
811 int i;
812 int volume;
813 switch (ch->volume) {
814 case 0:
815 volume = 0;
816 break;
817 case 1:
818 volume = 4;
819 break;
820 case 2:
821 volume = 2;
822 break;
823 case 3:
824 volume = 1;
825 break;
826 default:
827 volume = 3;
828 break;
829 }
830 int start;
831 int end;
832 switch (audio->style) {
833 case GB_AUDIO_DMG:
834 default:
835 ++ch->window;
836 ch->window &= 0x1F;
837 ch->sample = ch->wavedata8[ch->window >> 1];
838 if (!(ch->window & 1)) {
839 ch->sample >>= 4;
840 }
841 ch->sample &= 0xF;
842 break;
843 case GB_AUDIO_GBA:
844 if (ch->size) {
845 start = 7;
846 end = 0;
847 } else if (ch->bank) {
848 start = 7;
849 end = 4;
850 } else {
851 start = 3;
852 end = 0;
853 }
854 uint32_t bitsCarry = ch->wavedata32[end] & 0x000000F0;
855 uint32_t bits;
856 for (i = start; i >= end; --i) {
857 bits = ch->wavedata32[i] & 0x000000F0;
858 ch->wavedata32[i] = ((ch->wavedata32[i] & 0x0F0F0F0F) << 4) | ((ch->wavedata32[i] & 0xF0F0F000) >> 12);
859 ch->wavedata32[i] |= bitsCarry << 20;
860 bitsCarry = bits;
861 }
862 ch->sample = bitsCarry >> 4;
863 break;
864 }
865 ch->sample *= volume * 2;
866 audio->ch3.readable = true;
867 if (audio->style == GB_AUDIO_DMG) {
868 mTimingDeschedule(audio->timing, &audio->ch3Fade);
869 mTimingSchedule(timing, &audio->ch3Fade, 2 - cyclesLate);
870 }
871 int cycles = 2 * (2048 - ch->rate);
872 mTimingSchedule(timing, &audio->ch3Event, audio->timingFactor * cycles - cyclesLate);
873}
874static void _fadeChannel3(struct mTiming* timing, void* user, uint32_t cyclesLate) {
875 UNUSED(timing);
876 UNUSED(cyclesLate);
877 struct GBAudio* audio = user;
878 audio->ch3.readable = false;
879}
880
881static void _updateChannel4(struct mTiming* timing, void* user, uint32_t cyclesLate) {
882 struct GBAudio* audio = user;
883 struct GBAudioNoiseChannel* ch = &audio->ch4;
884
885 int32_t baseCycles = ch->ratio ? 2 * ch->ratio : 1;
886 baseCycles <<= ch->frequency;
887 baseCycles *= 8 * audio->timingFactor;
888 int32_t cycles = 0;
889
890 do {
891 int lsb = ch->lfsr & 1;
892 ch->sample = lsb * 0x8;
893 ch->sample *= ch->envelope.currentVolume;
894 ch->lfsr >>= 1;
895 ch->lfsr ^= (lsb * 0x60) << (ch->power ? 0 : 8);
896 cycles += baseCycles;
897 } while (cycles + baseCycles < audio->sampleInterval);
898 mTimingSchedule(timing, &audio->ch4Event, cycles - cyclesLate);
899}
900
901void GBAudioPSGSerialize(const struct GBAudio* audio, struct GBSerializedPSGState* state, uint32_t* flagsOut) {
902 uint32_t flags = 0;
903 uint32_t ch1Flags = 0;
904 uint32_t ch2Flags = 0;
905 uint32_t ch4Flags = 0;
906
907 flags = GBSerializedAudioFlagsSetFrame(flags, audio->frame);
908 STORE_32LE(audio->frameEvent.when - mTimingCurrentTime(audio->timing), 0, &state->ch1.nextFrame);
909
910 flags = GBSerializedAudioFlagsSetCh1Volume(flags, audio->ch1.envelope.currentVolume);
911 flags = GBSerializedAudioFlagsSetCh1Dead(flags, audio->ch1.envelope.dead);
912 flags = GBSerializedAudioFlagsSetCh1Hi(flags, audio->ch1.control.hi);
913 flags = GBSerializedAudioFlagsSetCh1SweepEnabled(flags, audio->ch1.sweep.enable);
914 flags = GBSerializedAudioFlagsSetCh1SweepOccurred(flags, audio->ch1.sweep.occurred);
915 ch1Flags = GBSerializedAudioEnvelopeSetLength(ch1Flags, audio->ch1.control.length);
916 ch1Flags = GBSerializedAudioEnvelopeSetNextStep(ch1Flags, audio->ch1.envelope.nextStep);
917 ch1Flags = GBSerializedAudioEnvelopeSetFrequency(ch1Flags, audio->ch1.sweep.realFrequency);
918 STORE_32LE(ch1Flags, 0, &state->ch1.envelope);
919 STORE_32LE(audio->ch1Event.when - mTimingCurrentTime(audio->timing), 0, &state->ch1.nextEvent);
920
921 flags = GBSerializedAudioFlagsSetCh2Volume(flags, audio->ch2.envelope.currentVolume);
922 flags = GBSerializedAudioFlagsSetCh2Dead(flags, audio->ch2.envelope.dead);
923 flags = GBSerializedAudioFlagsSetCh2Hi(flags, audio->ch2.control.hi);
924 ch2Flags = GBSerializedAudioEnvelopeSetLength(ch2Flags, audio->ch2.control.length);
925 ch2Flags = GBSerializedAudioEnvelopeSetNextStep(ch2Flags, audio->ch2.envelope.nextStep);
926 STORE_32LE(ch2Flags, 0, &state->ch2.envelope);
927 STORE_32LE(audio->ch2Event.when - mTimingCurrentTime(audio->timing), 0, &state->ch2.nextEvent);
928
929 flags = GBSerializedAudioFlagsSetCh3Readable(flags, audio->ch3.readable);
930 memcpy(state->ch3.wavebanks, audio->ch3.wavedata32, sizeof(state->ch3.wavebanks));
931 STORE_16LE(audio->ch3.length, 0, &state->ch3.length);
932 STORE_32LE(audio->ch3Event.when - mTimingCurrentTime(audio->timing), 0, &state->ch3.nextEvent);
933 STORE_32LE(audio->ch3Fade.when - mTimingCurrentTime(audio->timing), 0, &state->ch1.nextCh3Fade);
934
935 flags = GBSerializedAudioFlagsSetCh4Volume(flags, audio->ch4.envelope.currentVolume);
936 flags = GBSerializedAudioFlagsSetCh4Dead(flags, audio->ch4.envelope.dead);
937 STORE_32LE(audio->ch4.lfsr, 0, &state->ch4.lfsr);
938 ch4Flags = GBSerializedAudioEnvelopeSetLength(ch4Flags, audio->ch4.length);
939 ch4Flags = GBSerializedAudioEnvelopeSetNextStep(ch4Flags, audio->ch4.envelope.nextStep);
940 STORE_32LE(ch4Flags, 0, &state->ch4.envelope);
941 STORE_32LE(audio->ch4Event.when - mTimingCurrentTime(audio->timing), 0, &state->ch4.nextEvent);
942
943 STORE_32LE(flags, 0, flagsOut);
944}
945
946void GBAudioPSGDeserialize(struct GBAudio* audio, const struct GBSerializedPSGState* state, const uint32_t* flagsIn) {
947 uint32_t flags;
948 uint32_t ch1Flags = 0;
949 uint32_t ch2Flags = 0;
950 uint32_t ch4Flags = 0;
951 uint32_t when;
952
953 audio->playingCh1 = !!(*audio->nr52 & 0x0001);
954 audio->playingCh2 = !!(*audio->nr52 & 0x0002);
955 audio->playingCh3 = !!(*audio->nr52 & 0x0004);
956 audio->playingCh4 = !!(*audio->nr52 & 0x0008);
957 audio->enable = GBAudioEnableGetEnable(*audio->nr52);
958
959 LOAD_32LE(when, 0, &state->ch1.nextFrame);
960 mTimingSchedule(audio->timing, &audio->frameEvent, when);
961
962 LOAD_32LE(flags, 0, flagsIn);
963 LOAD_32LE(ch1Flags, 0, &state->ch1.envelope);
964 audio->ch1.envelope.currentVolume = GBSerializedAudioFlagsGetCh1Volume(flags);
965 audio->ch1.envelope.dead = GBSerializedAudioFlagsGetCh1Dead(flags);
966 audio->ch1.control.hi = GBSerializedAudioFlagsGetCh1Hi(flags);
967 audio->ch1.sweep.enable = GBSerializedAudioFlagsGetCh1SweepEnabled(flags);
968 audio->ch1.sweep.occurred = GBSerializedAudioFlagsGetCh1SweepOccurred(flags);
969 audio->ch1.control.length = GBSerializedAudioEnvelopeGetLength(ch1Flags);
970 audio->ch1.envelope.nextStep = GBSerializedAudioEnvelopeGetNextStep(ch1Flags);
971 audio->ch1.sweep.realFrequency = GBSerializedAudioEnvelopeGetFrequency(ch1Flags);
972 LOAD_32LE(when, 0, &state->ch1.nextEvent);
973 if (audio->ch1.envelope.dead < 2 && audio->playingCh1) {
974 mTimingSchedule(audio->timing, &audio->ch1Event, when);
975 }
976
977 LOAD_32LE(ch2Flags, 0, &state->ch2.envelope);
978 audio->ch2.envelope.currentVolume = GBSerializedAudioFlagsGetCh2Volume(flags);
979 audio->ch2.envelope.dead = GBSerializedAudioFlagsGetCh2Dead(flags);
980 audio->ch2.control.hi = GBSerializedAudioFlagsGetCh2Hi(flags);
981 audio->ch2.control.length = GBSerializedAudioEnvelopeGetLength(ch2Flags);
982 audio->ch2.envelope.nextStep = GBSerializedAudioEnvelopeGetNextStep(ch2Flags);
983 LOAD_32LE(when, 0, &state->ch2.nextEvent);
984 if (audio->ch2.envelope.dead < 2 && audio->playingCh2) {
985 mTimingSchedule(audio->timing, &audio->ch2Event, when);
986 }
987
988 audio->ch3.readable = GBSerializedAudioFlagsGetCh3Readable(flags);
989 // TODO: Big endian?
990 memcpy(audio->ch3.wavedata32, state->ch3.wavebanks, sizeof(audio->ch3.wavedata32));
991 LOAD_16LE(audio->ch3.length, 0, &state->ch3.length);
992 LOAD_32LE(when, 0, &state->ch3.nextEvent);
993 if (audio->playingCh3) {
994 mTimingSchedule(audio->timing, &audio->ch3Event, when);
995 }
996 LOAD_32LE(when, 0, &state->ch1.nextCh3Fade);
997 if (audio->ch3.readable && audio->style == GB_AUDIO_DMG) {
998 mTimingSchedule(audio->timing, &audio->ch3Fade, when);
999 }
1000
1001 LOAD_32LE(ch4Flags, 0, &state->ch4.envelope);
1002 audio->ch4.envelope.currentVolume = GBSerializedAudioFlagsGetCh4Volume(flags);
1003 audio->ch4.envelope.dead = GBSerializedAudioFlagsGetCh4Dead(flags);
1004 audio->ch4.length = GBSerializedAudioEnvelopeGetLength(ch4Flags);
1005 audio->ch4.envelope.nextStep = GBSerializedAudioEnvelopeGetNextStep(ch4Flags);
1006 LOAD_32LE(audio->ch4.lfsr, 0, &state->ch4.lfsr);
1007 LOAD_32LE(when, 0, &state->ch4.nextEvent);
1008 if (audio->ch4.envelope.dead < 2 && audio->playingCh4) {
1009 mTimingSchedule(audio->timing, &audio->ch4Event, when);
1010 }
1011}
1012
1013void GBAudioSerialize(const struct GBAudio* audio, struct GBSerializedState* state) {
1014 GBAudioPSGSerialize(audio, &state->audio.psg, &state->audio.flags);
1015 STORE_32LE(audio->sampleEvent.when - mTimingCurrentTime(audio->timing), 0, &state->audio.nextSample);
1016}
1017
1018void GBAudioDeserialize(struct GBAudio* audio, const struct GBSerializedState* state) {
1019 GBAudioPSGDeserialize(audio, &state->audio.psg, &state->audio.flags);
1020 uint32_t when;
1021 LOAD_32LE(when, 0, &state->audio.nextSample);
1022 mTimingSchedule(audio->timing, &audio->sampleEvent, when);
1023}