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
|
/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* 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.
*
* $URL$
* $Id$
*/
#include "sound/softsynth/cms.h"
#include "sound/null.h"
#include "common/textconsole.h"
#include "common/translation.h"
#include "common/debug.h"
// CMS/Gameblaster Emulation taken from DosBox
#define LEFT 0x00
#define RIGHT 0x01
static const byte envelope[8][64] = {
/* zero amplitude */
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
/* maximum amplitude */
{15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,
15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,
15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,
15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15, },
/* single decay */
{15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
/* repetitive decay */
{15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0,
15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0,
15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0,
15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0 },
/* single triangular */
{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15,
15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
/* repetitive triangular */
{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15,
15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15,
15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0 },
/* single attack */
{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
/* repetitive attack */
{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15 }
};
static const int amplitude_lookup[16] = {
0*32767/16, 1*32767/16, 2*32767/16, 3*32767/16,
4*32767/16, 5*32767/16, 6*32767/16, 7*32767/16,
8*32767/16, 9*32767/16, 10*32767/16, 11*32767/16,
12*32767/16, 13*32767/16, 14*32767/16, 15*32767/16
};
void CMSEmulator::portWrite(int port, int val) {
switch (port) {
case 0x220:
portWriteIntern(0, 1, val);
break;
case 0x221:
_saa1099[0].selected_reg = val & 0x1f;
if (_saa1099[0].selected_reg == 0x18 || _saa1099[0].selected_reg == 0x19) {
/* clock the envelope channels */
if (_saa1099[0].env_clock[0])
envelope(0, 0);
if (_saa1099[0].env_clock[1])
envelope(0, 1);
}
break;
case 0x222:
portWriteIntern(1, 1, val);
break;
case 0x223:
_saa1099[1].selected_reg = val & 0x1f;
if (_saa1099[1].selected_reg == 0x18 || _saa1099[1].selected_reg == 0x19) {
/* clock the envelope channels */
if (_saa1099[1].env_clock[0])
envelope(1, 0);
if (_saa1099[1].env_clock[1])
envelope(1, 1);
}
break;
default:
warning("CMSEmulator got port: 0x%X", port);
break;
}
}
void CMSEmulator::readBuffer(int16 *buffer, const int numSamples) {
update(0, &buffer[0], numSamples);
update(1, &buffer[0], numSamples);
}
void CMSEmulator::envelope(int chip, int ch) {
SAA1099 *saa = &_saa1099[chip];
if (saa->env_enable[ch]) {
int step, mode, mask;
mode = saa->env_mode[ch];
/* step from 0..63 and then loop in steps 32..63 */
step = saa->env_step[ch] = ((saa->env_step[ch] + 1) & 0x3f) | (saa->env_step[ch] & 0x20);
mask = 15;
if (saa->env_bits[ch])
mask &= ~1; /* 3 bit resolution, mask LSB */
saa->channels[ch*3+0].envelope[ LEFT] =
saa->channels[ch*3+1].envelope[ LEFT] =
saa->channels[ch*3+2].envelope[ LEFT] = ::envelope[mode][step] & mask;
if (saa->env_reverse_right[ch] & 0x01) {
saa->channels[ch*3+0].envelope[RIGHT] =
saa->channels[ch*3+1].envelope[RIGHT] =
saa->channels[ch*3+2].envelope[RIGHT] = (15 - ::envelope[mode][step]) & mask;
} else {
saa->channels[ch*3+0].envelope[RIGHT] =
saa->channels[ch*3+1].envelope[RIGHT] =
saa->channels[ch*3+2].envelope[RIGHT] = ::envelope[mode][step] & mask;
}
} else {
/* envelope mode off, set all envelope factors to 16 */
saa->channels[ch*3+0].envelope[ LEFT] =
saa->channels[ch*3+1].envelope[ LEFT] =
saa->channels[ch*3+2].envelope[ LEFT] =
saa->channels[ch*3+0].envelope[RIGHT] =
saa->channels[ch*3+1].envelope[RIGHT] =
saa->channels[ch*3+2].envelope[RIGHT] = 16;
}
}
void CMSEmulator::update(int chip, int16 *buffer, int length) {
struct SAA1099 *saa = &_saa1099[chip];
int j, ch;
/* if the channels are disabled we're done */
if (!saa->all_ch_enable) {
/* init output data */
if (chip == 0) {
memset(buffer, 0, sizeof(int16)*length*2);
}
return;
}
if (chip == 0) {
memset(buffer, 0, sizeof(int16)*length*2);
}
for (ch = 0; ch < 2; ch++) {
switch (saa->noise_params[ch]) {
case 0: saa->noise[ch].freq = 31250.0 * 2; break;
case 1: saa->noise[ch].freq = 15625.0 * 2; break;
case 2: saa->noise[ch].freq = 7812.5 * 2; break;
case 3: saa->noise[ch].freq = saa->channels[ch * 3].freq; break;
}
}
/* fill all data needed */
for (j = 0; j < length; ++j) {
int output_l = 0, output_r = 0;
/* for each channel */
for (ch = 0; ch < 6; ch++) {
if (saa->channels[ch].freq == 0.0)
saa->channels[ch].freq = (double)((2 * 15625) << saa->channels[ch].octave) /
(511.0 - (double)saa->channels[ch].frequency);
/* check the actual position in the square wave */
saa->channels[ch].counter -= saa->channels[ch].freq;
while (saa->channels[ch].counter < 0) {
/* calculate new frequency now after the half wave is updated */
saa->channels[ch].freq = (double)((2 * 15625) << saa->channels[ch].octave) /
(511.0 - (double)saa->channels[ch].frequency);
saa->channels[ch].counter += _sampleRate;
saa->channels[ch].level ^= 1;
/* eventually clock the envelope counters */
if (ch == 1 && saa->env_clock[0] == 0)
envelope(chip, 0);
if (ch == 4 && saa->env_clock[1] == 0)
envelope(chip, 1);
}
/* if the noise is enabled */
if (saa->channels[ch].noise_enable) {
/* if the noise level is high (noise 0: chan 0-2, noise 1: chan 3-5) */
if (saa->noise[ch/3].level & 1) {
/* subtract to avoid overflows, also use only half amplitude */
output_l -= saa->channels[ch].amplitude[ LEFT] * saa->channels[ch].envelope[ LEFT] / 16 / 2;
output_r -= saa->channels[ch].amplitude[RIGHT] * saa->channels[ch].envelope[RIGHT] / 16 / 2;
}
}
/* if the square wave is enabled */
if (saa->channels[ch].freq_enable) {
/* if the channel level is high */
if (saa->channels[ch].level & 1) {
output_l += saa->channels[ch].amplitude[ LEFT] * saa->channels[ch].envelope[ LEFT] / 16;
output_r += saa->channels[ch].amplitude[RIGHT] * saa->channels[ch].envelope[RIGHT] / 16;
}
}
}
for (ch = 0; ch < 2; ch++) {
/* check the actual position in noise generator */
saa->noise[ch].counter -= saa->noise[ch].freq;
while (saa->noise[ch].counter < 0) {
saa->noise[ch].counter += _sampleRate;
if (((saa->noise[ch].level & 0x4000) == 0) == ((saa->noise[ch].level & 0x0040) == 0) )
saa->noise[ch].level = (saa->noise[ch].level << 1) | 1;
else
saa->noise[ch].level <<= 1;
}
}
/* write sound data to the buffer */
buffer[j*2] += output_l / 6;
buffer[j*2+1] += output_r / 6;
}
}
void CMSEmulator::portWriteIntern(int chip, int offset, int data) {
SAA1099 *saa = &_saa1099[chip];
int reg = saa->selected_reg;
int ch;
switch (reg) {
/* channel i amplitude */
case 0x00:
case 0x01:
case 0x02:
case 0x03:
case 0x04:
case 0x05:
ch = reg & 7;
saa->channels[ch].amplitude[LEFT] = amplitude_lookup[data & 0x0f];
saa->channels[ch].amplitude[RIGHT] = amplitude_lookup[(data >> 4) & 0x0f];
break;
/* channel i frequency */
case 0x08:
case 0x09:
case 0x0a:
case 0x0b:
case 0x0c:
case 0x0d:
ch = reg & 7;
saa->channels[ch].frequency = data & 0xff;
break;
/* channel i octave */
case 0x10:
case 0x11:
case 0x12:
ch = (reg - 0x10) << 1;
saa->channels[ch + 0].octave = data & 0x07;
saa->channels[ch + 1].octave = (data >> 4) & 0x07;
break;
/* channel i frequency enable */
case 0x14:
saa->channels[0].freq_enable = data & 0x01;
saa->channels[1].freq_enable = data & 0x02;
saa->channels[2].freq_enable = data & 0x04;
saa->channels[3].freq_enable = data & 0x08;
saa->channels[4].freq_enable = data & 0x10;
saa->channels[5].freq_enable = data & 0x20;
break;
/* channel i noise enable */
case 0x15:
saa->channels[0].noise_enable = data & 0x01;
saa->channels[1].noise_enable = data & 0x02;
saa->channels[2].noise_enable = data & 0x04;
saa->channels[3].noise_enable = data & 0x08;
saa->channels[4].noise_enable = data & 0x10;
saa->channels[5].noise_enable = data & 0x20;
break;
/* noise generators parameters */
case 0x16:
saa->noise_params[0] = data & 0x03;
saa->noise_params[1] = (data >> 4) & 0x03;
break;
/* envelope generators parameters */
case 0x18:
case 0x19:
ch = reg - 0x18;
saa->env_reverse_right[ch] = data & 0x01;
saa->env_mode[ch] = (data >> 1) & 0x07;
saa->env_bits[ch] = data & 0x10;
saa->env_clock[ch] = data & 0x20;
saa->env_enable[ch] = data & 0x80;
/* reset the envelope */
saa->env_step[ch] = 0;
break;
/* channels enable & reset generators */
case 0x1c:
saa->all_ch_enable = data & 0x01;
saa->sync_state = data & 0x02;
if (data & 0x02) {
int i;
/* Synch & Reset generators */
for (i = 0; i < 6; i++) {
saa->channels[i].level = 0;
saa->channels[i].counter = 0.0;
}
}
break;
default:
// The CMS allows all registers to be written, so we just output some debug
// message here
debug(5, "CMS Unknown write to reg %x with %x",reg, data);
}
}
class CMSMusicPlugin : public NullMusicPlugin {
public:
const char *getName() const {
return _s("Creative Music System Emulator");
}
const char *getId() const {
return "cms";
}
MusicDevices getDevices() const;
};
MusicDevices CMSMusicPlugin::getDevices() const {
MusicDevices devices;
devices.push_back(MusicDevice(this, "", MT_CMS));
return devices;
}
//#if PLUGIN_ENABLED_DYNAMIC(CMS)
//REGISTER_PLUGIN_DYNAMIC(CMS, PLUGIN_TYPE_MUSIC, CMSMusicPlugin);
//#else
REGISTER_PLUGIN_STATIC(CMS, PLUGIN_TYPE_MUSIC, CMSMusicPlugin);
//#endif
|
