-
Notifications
You must be signed in to change notification settings - Fork 3
/
ym2413.c
397 lines (325 loc) · 15.5 KB
/
ym2413.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
/*
Copyright (C) 2000 Charles Mac Donald
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
YM2413 (OPLL) emulator
by Charles Mac Donald
E-mail: cgfm2@hooked.net
WWW: http://cgfm2.emuviews.com
Change log:
[061300]
- Fixed bug where channel numbers larger than 9 could be written to
register groups $10-18, $20-28, $30-38.
[060800]
- Now the YM2413 chip number is passed to the OPL_WRITE macro,
and the user instrument data is stored in the YM2413 context,
both for multiple YM2413 emulation.
[060100]
- Added alternate instrument table taken from Allegro's 'fm_inst.h'.
- Changed source so it can compile seperately from SMS Plus.
- Added 'ym2413_reset' function and changed ym2413_init.
Known issues:
- The sustain on/off flag (bit 5 of register group $20-28) is not
emulated. According to the manual, the release rate is set to
five when this bit is set.
- The table of fixed instrument values probably need to be compared
against a real YM2413, so they can be hand-tuned.
- The rhythm instruments sound good, but are too loud.
The same settings are used for channels 7, 8, 9, which can't be right.
I based the YM2413 emulation on the following documents. If you want
to improve it or make changes, I'd advise reading the following:
- Yamaha's YMF-272 (OPL-3) programmer's manual. (ymf272.pdf)
(Has useful table of how the operators map to YM3812 registers)
- Yamaha's YM2413 programmer's manual. (ym2413.lzh)
- Vladimir Arnost's OPL-3 programmer's guide. (opl3.txt)
(Explains operator allocation in rhythm mode)
- The YM2413 emulation from MAME. (ym2413.c/2413intf.h)
*/
#include "shared.h"
/* You can replace this to output to another YM3812 emulator
or a perhaps a real OPL-2/OPL-3 sound chip */
#if USE_ADLIB
#define OPL_WRITE(c,r,d) { outp(0x388+c*2, r); outp(0x389+c*2, d); }
#else
#define OPL_WRITE(c,r,d) OPLWriteReg(ym3812, r, d)
#endif
/* YM2413 chip contexts */
t_ym2413 ym2413[MAX_YM2413];
/* Fixed instrument settings, from MAME's YM2413 emulation */
/* This might need some tweaking... */
unsigned char table[16][11] =
{
/* 20 23 40 43 60 63 80 83 E0 E3 C0 */
{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
#if 1 /* Instrument settings from MAME */
{ 0x01, 0x22, 0x23, 0x07, 0xF0, 0xF0, 0x07, 0x18, 0x00, 0x00, 0x00 },
{ 0x23, 0x01, 0x68, 0x05, 0xF2, 0x74, 0x6C, 0x89, 0x00, 0x00, 0x00 },
{ 0x13, 0x11, 0x25, 0x00, 0xD2, 0xB2, 0xF4, 0xF4, 0x00, 0x00, 0x00 },
{ 0x22, 0x21, 0x1B, 0x05, 0xC0, 0xA1, 0x18, 0x08, 0x00, 0x00, 0x00 },
{ 0x22, 0x21, 0x2C, 0x03, 0xD2, 0xA1, 0x18, 0x57, 0x00, 0x00, 0x00 },
{ 0x01, 0x22, 0xBA, 0x01, 0xF1, 0xF1, 0x1E, 0x04, 0x00, 0x00, 0x00 },
{ 0x21, 0x21, 0x28, 0x06, 0xF1, 0xF1, 0x6B, 0x3E, 0x00, 0x00, 0x00 },
{ 0x27, 0x21, 0x60, 0x00, 0xF0, 0xF0, 0x0D, 0x0F, 0x00, 0x00, 0x00 },
{ 0x20, 0x21, 0x2B, 0x06, 0x85, 0xF1, 0x6D, 0x89, 0x00, 0x00, 0x00 },
{ 0x01, 0x21, 0xBF, 0x02, 0x53, 0x62, 0x5F, 0xAE, 0x01, 0x00, 0x00 },
{ 0x23, 0x21, 0x70, 0x07, 0xD4, 0xA3, 0x4E, 0x64, 0x01, 0x00, 0x00 },
{ 0x2B, 0x21, 0xA4, 0x07, 0xF6, 0x93, 0x5C, 0x4D, 0x00, 0x00, 0x00 },
{ 0x21, 0x23, 0xAD, 0x07, 0x77, 0xF1, 0x18, 0x37, 0x00, 0x00, 0x00 },
{ 0x21, 0x21, 0x2A, 0x03, 0xF3, 0xE2, 0x29, 0x46, 0x00, 0x00, 0x00 },
{ 0x21, 0x23, 0x37, 0x03, 0xF3, 0xE2, 0x29, 0x46, 0x00, 0x00, 0x00 },
#else /* Instrument settings from Allegro */
{ 0x31, 0x21, 0x15, 0x09, 0xdd, 0x56, 0x13, 0x26, 0x01, 0x00, 0x08 }, /* Violin */
{ 0x03, 0x11, 0x54, 0x09, 0xf3, 0xf1, 0x9a, 0xe7, 0x01, 0x00, 0x0c }, /* Acoustic Guitar(steel) */
{ 0x21, 0x21, 0x8f, 0x0c, 0xf2, 0xf2, 0x45, 0x76, 0x00, 0x00, 0x08 }, /* Acoustic Grand */
{ 0xe1, 0xe1, 0x46, 0x09, 0x88, 0x65, 0x5f, 0x1a, 0x00, 0x00, 0x00 }, /* Flute */
{ 0x32, 0x21, 0x90, 0x09, 0x9b, 0x72, 0x21, 0x17, 0x00, 0x00, 0x04 }, /* Clarinet */
{ 0x21, 0x21, 0x4b, 0x09, 0xaa, 0x8f, 0x16, 0x0a, 0x01, 0x00, 0x08 }, /* Oboe */
{ 0x21, 0x21, 0x92, 0x0a, 0x85, 0x8f, 0x17, 0x09, 0x00, 0x00, 0x0c }, /* Trumpet */
{ 0x23, 0xb1, 0x93, 0x09, 0x97, 0x55, 0x23, 0x14, 0x01, 0x00, 0x04 }, /* Church Organ */
{ 0x21, 0x21, 0x9b, 0x09, 0x61, 0x7f, 0x6a, 0x0a, 0x00, 0x00, 0x02 }, /* French Horn */
{ 0x71, 0x72, 0x57, 0x09, 0x54, 0x7a, 0x05, 0x05, 0x00, 0x00, 0x0c }, /* Synth Voice */
{ 0x21, 0x36, 0x80, 0x17, 0xa2, 0xf1, 0x01, 0xd5, 0x00, 0x00, 0x08 }, /* Harpsichord */
{ 0x18, 0x81, 0x62, 0x09, 0xf3, 0xf2, 0xe6, 0xf6, 0x00, 0x00, 0x00 }, /* Vibraphone */
{ 0x31, 0x31, 0x8b, 0x09, 0xf4, 0xf1, 0xe8, 0x78, 0x00, 0x00, 0x0a }, /* Synth Bass 1 */
{ 0x21, 0xa2, 0x1e, 0x09, 0x94, 0xc3, 0x06, 0xa6, 0x00, 0x00, 0x02 }, /* Acoustic Bass */
{ 0x03, 0x21, 0x87, 0x89, 0xf6, 0xf3, 0x22, 0xf8, 0x01, 0x00, 0x06 }, /* Electric Guitar(clean) */
#endif
};
/*--------------------------------------------------------------------------*/
void ym2413_init(int count)
{
int n;
for(n = 0; n < count; n += 1)
{
/* Reset YM2413 data */
ym2413_reset(n);
}
}
void ym2413_reset(int chip)
{
int n;
/* Point to current YM2413 context */
t_ym2413 *opll = &ym2413[chip];
/* Clear channel data context */
memset(opll, 0, sizeof(t_ym2413));
/* Clear all YM3812 registers */
for(n = 0; n < 0x100; n += 1)
{
OPL_WRITE(chip, n, 0x00);
}
/* Turn off rhythm mode and key-on bits */
opll->rhythm = 0;
OPL_WRITE(chip, 0xBD, 0x00);
/* Enable waveform select */
OPL_WRITE(chip, 0x01, 0x20);
}
void ym2413_write(int chip, int address, int data)
{
/* Point to current YM2413 context */
t_ym2413 *opll = &ym2413[chip];
if(address & 1) /* Data port */
{
/* Store register data */
opll->reg[opll->latch] = data;
switch(opll->latch & 0x30)
{
case 0x00: /* User instrument registers */
switch(opll->latch & 0x0F)
{
case 0x00: /* Misc. ctrl. (modulator) */
case 0x01: /* Misc. ctrl. (carrier) */
case 0x02: /* Key scale level and total level (modulator) */
case 0x04: /* Attack / Decay (modulator) */
case 0x05: /* Attack / Decay (carrier) */
case 0x06: /* Sustain / Release (modulator) */
case 0x07: /* Sustain / Release (carrier) */
opll->user[(opll->latch & 0x07)] = data;
break;
case 0x03: /* Key scale level, carrier/modulator waveform, feedback */
/* Key scale level (carrier) */
/* Don't touch the total level (channel volume) */
opll->user[3] = (opll->user[3] & 0x3F) | (data & 0xC0);
/* Waveform select for the modulator */
opll->user[8] = (data >> 3) & 1;
/* Waveform select for the carrier */
opll->user[9] = (data >> 4) & 1;
/* Store feedback level in YM3812 format */
opll->user[10] = ((data & 0x07) << 1) & 0x0E;
break;
case 0x0E: /* Rhythm enable and key-on bits */
if((data & 0x20) && (opll->rhythm == 0))
{
opll->rhythm = 1;
rhythm_mode_init(chip);
}
else
{
opll->rhythm = 0;
}
OPL_WRITE(chip, 0xBD, (data & 0x3F));
break;
}
/* If the user instrument registers were accessed, then
go through each channel and update the ones that were
currently using the user instrument. We can skip the
last three channels in rhythm mode since they can
only use percussion sounds anyways. */
if(opll->latch <= 0x07)
{
int x;
for(x = 0; x < ((opll->reg[0x0E] & 0x20) ? 6 : 9); x += 1)
if(opll->channel[x].instrument == 0x00)
load_instrument(chip, x, 0x00, opll->channel[x].volume);
}
break;
case 0x10: /* Channel Frequency (LSB) */
case 0x20: /* Channel Frequency (MSB) + key-on and sustain control */
{
int block;
int frequency;
int ch = (opll->latch & 0x0F);
/* Ensure proper channel range */
if(ch > 0x08) break;
/* Get YM2413 channel frequency */
frequency = ((opll->reg[0x10 + ch] & 0xFF) | ((opll->reg[0x20 + ch] & 0x01) << 8));
/* Scale 9 bit frequency to 10 bits */
frequency = (frequency << 1) & 0x1FFF;
/* Get YM2413 block */
block = (opll->reg[0x20 + ch] >> 1) & 7;
/* Add in block */
frequency |= (block << 10);
/* Add key-on flag */
if(opll->reg[0x20 + ch] & 0x10) frequency |= 0x2000;
/* Save current frequency/block/key-on setting */
opll->channel[ch].frequency = (frequency & 0x3FFF);
/* TODO: Handle sustain flag (bit 5) before key-on */
/* Write changes to YM3812 */
OPL_WRITE(chip, 0xA0 + ch, (opll->channel[ch].frequency >> 0) & 0xFF);
OPL_WRITE(chip, 0xB0 + ch, (opll->channel[ch].frequency >> 8) & 0xFF);
}
break;
case 0x30: /* Channel Volume Level and Instrument Select */
/* Ensure proper channel range */
if(opll->latch > 0x38) break;
/* If we're accessing registers 36, 37, or 38, and we're
in rhythm mode, then update the individual volume
settings. */
if((opll->latch >= 0x36) && (opll->reg[0x0E] & 0x20))
{
switch(opll->latch & 0x0F)
{
case 0x06: /* Bass drum */
OPL_WRITE(chip, 0x53, ((data >> 0) & 0x0F) << 2);
break;
case 0x07: /* High hat and snare drum */
OPL_WRITE(chip, 0x51, ((data >> 4) & 0x0F) << 2);
OPL_WRITE(chip, 0x54, ((data >> 0) & 0x0F) << 2);
break;
case 0x08: /* Tom-top and top cymbal */
OPL_WRITE(chip, 0x52, ((data >> 4) & 0x0F) << 2);
OPL_WRITE(chip, 0x55, ((data >> 0) & 0x0F) << 2);
break;
}
}
else /* Set the new instrument and volume for this channel */
{
int ch = (opll->latch & 0x0F);
int inst = (data >> 4) & 0x0F;
int vol = (data & 0x0F) << 2;
load_instrument(chip, ch, inst, vol);
}
break;
}
}
else /* Register latch */
{
opll->latch = (data & 0x3F);
}
}
void rhythm_mode_init(int chip)
{
/* Point to current YM2413 context */
t_ym2413 *opll = &ym2413[chip];
/* Load instrument settings for channel seven. (Bass drum) */
OPL_WRITE(chip, 0x30, 0x13);
OPL_WRITE(chip, 0x33, 0x11);
OPL_WRITE(chip, 0x50, 0x25);
OPL_WRITE(chip, 0x53, ((opll->reg[0x36] >> 0) & 0x0F) << 2);
OPL_WRITE(chip, 0x70, 0xD7);
OPL_WRITE(chip, 0x73, 0xB7);
OPL_WRITE(chip, 0x90, 0xF4);
OPL_WRITE(chip, 0x93, 0xF4);
OPL_WRITE(chip, 0xF0, 0x00);
OPL_WRITE(chip, 0xF3, 0x00);
OPL_WRITE(chip, 0xC6, 0x00);
/* Use old frequency, but strip key-on bit */
OPL_WRITE(chip, 0xA6, (opll->channel[6].frequency >> 0) & 0xFF);
OPL_WRITE(chip, 0xB6, (opll->channel[6].frequency >> 8) & 0x1F);
/* Load instrument settings for channel eight. (High hat and snare drum) */
OPL_WRITE(chip, 0x31, 0x13);
OPL_WRITE(chip, 0x34, 0x11);
OPL_WRITE(chip, 0x51, ((opll->reg[0x37] >> 4) & 0x0f) << 2);
OPL_WRITE(chip, 0x54, ((opll->reg[0x37] >> 0) & 0x0f) << 2);
OPL_WRITE(chip, 0x71, 0xD7);
OPL_WRITE(chip, 0x74, 0xB7);
OPL_WRITE(chip, 0x91, 0xF4);
OPL_WRITE(chip, 0x94, 0xF4);
OPL_WRITE(chip, 0xF1, 0x00);
OPL_WRITE(chip, 0xF4, 0x00);
OPL_WRITE(chip, 0xC7, 0x00);
/* Use old frequency, but strip key-on bit */
OPL_WRITE(chip, 0xA7, (opll->channel[7].frequency >> 0) & 0xFF);
OPL_WRITE(chip, 0xB7, (opll->channel[7].frequency >> 8) & 0x1F);
/* Load instrument settings for channel nine. (Tom-tom and top cymbal) */
OPL_WRITE(chip, 0x32, 0x13);
OPL_WRITE(chip, 0x35, 0x11);
OPL_WRITE(chip, 0x52, ((opll->reg[0x38] >> 4) & 0x0F) << 2);
OPL_WRITE(chip, 0x55, ((opll->reg[0x38] >> 0) & 0x0F) << 2);
OPL_WRITE(chip, 0x72, 0xD7);
OPL_WRITE(chip, 0x75, 0xB7);
OPL_WRITE(chip, 0x92, 0xF4);
OPL_WRITE(chip, 0x95, 0xF4);
OPL_WRITE(chip, 0xF2, 0x00);
OPL_WRITE(chip, 0xF5, 0x00);
OPL_WRITE(chip, 0xC8, 0x00);
/* Use old frequency, but strip key-on bit */
OPL_WRITE(chip, 0xA8, (opll->channel[8].frequency >> 0) & 0xFF);
OPL_WRITE(chip, 0xB8, (opll->channel[8].frequency >> 8) & 0x1F);
}
/* channel (0-9), instrument (0-F), volume (0-3F, YM3812 format) */
void load_instrument(int chip, int ch, int inst, int vol)
{
/* Point to current YM2413 context */
t_ym2413 *opll = &ym2413[chip];
/* Point to fixed instrument or user table */
unsigned char *param = (inst == 0) ? &opll->user[0] : &table[inst][0];
/* Maps channels to operator registers */
unsigned char ch2op[] = {0, 1, 2, 8, 9, 10, 16, 17, 18};
/* Make operator offset from requested channel */
int op = ch2op[ch];
/* Store volume level */
opll->channel[ch].volume = (vol & 0x3F);
/* Store instrument number */
opll->channel[ch].instrument = (inst & 0x0F);
/* Update instrument settings, except frequency registers */
OPL_WRITE(chip, 0x20 + op, param[0]);
OPL_WRITE(chip, 0x23 + op, param[1]);
OPL_WRITE(chip, 0x40 + op, param[2]);
OPL_WRITE(chip, 0x43 + op, (param[3] & 0xC0) | opll->channel[ch].volume);
OPL_WRITE(chip, 0x60 + op, param[4]);
OPL_WRITE(chip, 0x63 + op, param[5]);
OPL_WRITE(chip, 0x80 + op, param[6]);
OPL_WRITE(chip, 0x83 + op, param[7]);
OPL_WRITE(chip, 0xE0 + op, param[8]);
OPL_WRITE(chip, 0xE3 + op, param[9]);
OPL_WRITE(chip, 0xC0 + ch, param[10]);
}