1 ============================================= 2 Sound Blaster Audigy mixer / default DSP code 3 ============================================= 4 5 This is based on sb-live-mixer.rst. 6 7 The EMU10K2 chips have a DSP part which can be programmed to support 8 various ways of sample processing, which is described here. 9 (This article does not deal with the overall functionality of the 10 EMU10K2 chips. See the manuals section for further details.) 11 12 The ALSA driver programs this portion of chip by default code 13 (can be altered later) which offers the following functionality: 14 15 16 Digital mixer controls 17 ====================== 18 19 These controls are built using the DSP instructions. They offer extended 20 functionality. Only the default built-in code in the ALSA driver is described 21 here. Note that the controls work as attenuators: the maximum value is the 22 neutral position leaving the signal unchanged. Note that if the same destination 23 is mentioned in multiple controls, the signal is accumulated and can be clipped 24 (set to maximal or minimal value without checking for overflow). 25 26 27 Explanation of used abbreviations: 28 29 DAC 30 digital to analog converter 31 ADC 32 analog to digital converter 33 I2S 34 one-way three wire serial bus for digital sound by Philips Semiconductors 35 (this standard is used for connecting standalone D/A and A/D converters) 36 LFE 37 low frequency effects (used as subwoofer signal) 38 AC97 39 a chip containing an analog mixer, D/A and A/D converters 40 IEC958 41 S/PDIF 42 FX-bus 43 the EMU10K2 chip has an effect bus containing 64 accumulators. 44 Each of the synthesizer voices can feed its output to these accumulators 45 and the DSP microcontroller can operate with the resulting sum. 46 47 name='PCM Front Playback Volume',index=0 48 ---------------------------------------- 49 This control is used to attenuate samples from left and right front PCM FX-bus 50 accumulators. ALSA uses accumulators 8 and 9 for left and right front PCM 51 samples for 5.1 playback. The result samples are forwarded to the front speakers. 52 53 name='PCM Surround Playback Volume',index=0 54 ------------------------------------------- 55 This control is used to attenuate samples from left and right surround PCM FX-bus 56 accumulators. ALSA uses accumulators 2 and 3 for left and right surround PCM 57 samples for 5.1 playback. The result samples are forwarded to the surround (rear) 58 speakers. 59 60 name='PCM Side Playback Volume',index=0 61 --------------------------------------- 62 This control is used to attenuate samples from left and right side PCM FX-bus 63 accumulators. ALSA uses accumulators 14 and 15 for left and right side PCM 64 samples for 7.1 playback. The result samples are forwarded to the side speakers. 65 66 name='PCM Center Playback Volume',index=0 67 ----------------------------------------- 68 This control is used to attenuate samples from center PCM FX-bus accumulator. 69 ALSA uses accumulator 6 for center PCM samples for 5.1 playback. The result 70 samples are forwarded to the center speaker. 71 72 name='PCM LFE Playback Volume',index=0 73 -------------------------------------- 74 This control is used to attenuate sample for LFE PCM FX-bus accumulator. 75 ALSA uses accumulator 7 for LFE PCM samples for 5.1 playback. The result 76 samples are forwarded to the subwoofer. 77 78 name='PCM Playback Volume',index=0 79 ---------------------------------- 80 This control is used to attenuate samples from left and right PCM FX-bus 81 accumulators. ALSA uses accumulators 0 and 1 for left and right PCM samples for 82 stereo playback. The result samples are forwarded to the front speakers. 83 84 name='PCM Capture Volume',index=0 85 --------------------------------- 86 This control is used to attenuate samples from left and right PCM FX-bus 87 accumulators. ALSA uses accumulators 0 and 1 for left and right PCM samples for 88 stereo playback. The result is forwarded to the standard capture PCM device. 89 90 name='Music Playback Volume',index=0 91 ------------------------------------ 92 This control is used to attenuate samples from left and right MIDI FX-bus 93 accumulators. ALSA uses accumulators 4 and 5 for left and right MIDI samples. 94 The result samples are forwarded to the virtual stereo mixer. 95 96 name='Music Capture Volume',index=0 97 ----------------------------------- 98 These controls are used to attenuate samples from left and right MIDI FX-bus 99 accumulator. ALSA uses accumulators 4 and 5 for left and right MIDI samples. 100 The result is forwarded to the standard capture PCM device. 101 102 name='Mic Playback Volume',index=0 103 ---------------------------------- 104 This control is used to attenuate samples from left and right Mic input of 105 the AC97 codec. The result samples are forwarded to the virtual stereo mixer. 106 107 name='Mic Capture Volume',index=0 108 --------------------------------- 109 This control is used to attenuate samples from left and right Mic input of 110 the AC97 codec. The result is forwarded to the standard capture PCM device. 111 112 The original samples are also forwarded to the Mic capture PCM device (device 1; 113 16bit/8KHz mono) without volume control. 114 115 name='Audigy CD Playback Volume',index=0 116 ---------------------------------------- 117 This control is used to attenuate samples from left and right IEC958 TTL 118 digital inputs (usually used by a CDROM drive). The result samples are 119 forwarded to the virtual stereo mixer. 120 121 name='Audigy CD Capture Volume',index=0 122 --------------------------------------- 123 This control is used to attenuate samples from left and right IEC958 TTL 124 digital inputs (usually used by a CDROM drive). The result is forwarded 125 to the standard capture PCM device. 126 127 name='IEC958 Optical Playback Volume',index=0 128 --------------------------------------------- 129 This control is used to attenuate samples from left and right IEC958 optical 130 digital input. The result samples are forwarded to the virtual stereo mixer. 131 132 name='IEC958 Optical Capture Volume',index=0 133 -------------------------------------------- 134 This control is used to attenuate samples from left and right IEC958 optical 135 digital inputs. The result is forwarded to the standard capture PCM device. 136 137 name='Line2 Playback Volume',index=0 138 ------------------------------------ 139 This control is used to attenuate samples from left and right I2S ADC 140 inputs (on the AudigyDrive). The result samples are forwarded to the virtual 141 stereo mixer. 142 143 name='Line2 Capture Volume',index=1 144 ----------------------------------- 145 This control is used to attenuate samples from left and right I2S ADC 146 inputs (on the AudigyDrive). The result is forwarded to the standard capture 147 PCM device. 148 149 name='Analog Mix Playback Volume',index=0 150 ----------------------------------------- 151 This control is used to attenuate samples from left and right I2S ADC 152 inputs from Philips ADC. The result samples are forwarded to the virtual 153 stereo mixer. This contains mix from analog sources like CD, Line In, Aux, .... 154 155 name='Analog Mix Capture Volume',index=1 156 ---------------------------------------- 157 This control is used to attenuate samples from left and right I2S ADC 158 inputs Philips ADC. The result is forwarded to the standard capture PCM device. 159 160 name='Aux2 Playback Volume',index=0 161 ----------------------------------- 162 This control is used to attenuate samples from left and right I2S ADC 163 inputs (on the AudigyDrive). The result samples are forwarded to the virtual 164 stereo mixer. 165 166 name='Aux2 Capture Volume',index=1 167 ---------------------------------- 168 This control is used to attenuate samples from left and right I2S ADC 169 inputs (on the AudigyDrive). The result is forwarded to the standard capture 170 PCM device. 171 172 name='Front Playback Volume',index=0 173 ------------------------------------ 174 This control is used to attenuate samples from the virtual stereo mixer. 175 The result samples are forwarded to the front speakers. 176 177 name='Surround Playback Volume',index=0 178 --------------------------------------- 179 This control is used to attenuate samples from the virtual stereo mixer. 180 The result samples are forwarded to the surround (rear) speakers. 181 182 name='Side Playback Volume',index=0 183 ----------------------------------- 184 This control is used to attenuate samples from the virtual stereo mixer. 185 The result samples are forwarded to the side speakers. 186 187 name='Center Playback Volume',index=0 188 ------------------------------------- 189 This control is used to attenuate samples from the virtual stereo mixer. 190 The result samples are forwarded to the center speaker. 191 192 name='LFE Playback Volume',index=0 193 ---------------------------------- 194 This control is used to attenuate samples from the virtual stereo mixer. 195 The result samples are forwarded to the subwoofer. 196 197 name='Tone Control - Switch',index=0 198 ------------------------------------ 199 This control turns the tone control on or off. The samples forwarded to 200 the speaker outputs are affected. 201 202 name='Tone Control - Bass',index=0 203 ---------------------------------- 204 This control sets the bass intensity. There is no neutral value!! 205 When the tone control code is activated, the samples are always modified. 206 The closest value to pure signal is 20. 207 208 name='Tone Control - Treble',index=0 209 ------------------------------------ 210 This control sets the treble intensity. There is no neutral value!! 211 When the tone control code is activated, the samples are always modified. 212 The closest value to pure signal is 20. 213 214 name='Master Playback Volume',index=0 215 ------------------------------------- 216 This control is used to attenuate samples forwarded to the speaker outputs. 217 218 name='IEC958 Optical Raw Playback Switch',index=0 219 ------------------------------------------------- 220 If this switch is on, then the samples for the IEC958 (S/PDIF) digital 221 output are taken only from the raw iec958 ALSA PCM device (which uses 222 accumulators 20 and 21 for left and right PCM by default). 223 224 225 PCM stream related controls 226 =========================== 227 228 name='EMU10K1 PCM Volume',index 0-31 229 ------------------------------------ 230 Channel volume attenuation in range 0-0x1fffd. The middle value (no 231 attenuation) is default. The channel mapping for three values is 232 as follows: 233 234 * 0 - mono, default 0xffff (no attenuation) 235 * 1 - left, default 0xffff (no attenuation) 236 * 2 - right, default 0xffff (no attenuation) 237 238 name='EMU10K1 PCM Send Routing',index 0-31 239 ------------------------------------------ 240 This control specifies the destination - FX-bus accumulators. There are 24 241 values in this mapping: 242 243 * 0 - mono, A destination (FX-bus 0-63), default 0 244 * 1 - mono, B destination (FX-bus 0-63), default 1 245 * 2 - mono, C destination (FX-bus 0-63), default 2 246 * 3 - mono, D destination (FX-bus 0-63), default 3 247 * 4 - mono, E destination (FX-bus 0-63), default 4 248 * 5 - mono, F destination (FX-bus 0-63), default 5 249 * 6 - mono, G destination (FX-bus 0-63), default 6 250 * 7 - mono, H destination (FX-bus 0-63), default 7 251 * 8 - left, A destination (FX-bus 0-63), default 0 252 * 9 - left, B destination (FX-bus 0-63), default 1 253 * 10 - left, C destination (FX-bus 0-63), default 2 254 * 11 - left, D destination (FX-bus 0-63), default 3 255 * 12 - left, E destination (FX-bus 0-63), default 4 256 * 13 - left, F destination (FX-bus 0-63), default 5 257 * 14 - left, G destination (FX-bus 0-63), default 6 258 * 15 - left, H destination (FX-bus 0-63), default 7 259 * 16 - right, A destination (FX-bus 0-63), default 0 260 * 17 - right, B destination (FX-bus 0-63), default 1 261 * 18 - right, C destination (FX-bus 0-63), default 2 262 * 19 - right, D destination (FX-bus 0-63), default 3 263 * 20 - right, E destination (FX-bus 0-63), default 4 264 * 21 - right, F destination (FX-bus 0-63), default 5 265 * 22 - right, G destination (FX-bus 0-63), default 6 266 * 23 - right, H destination (FX-bus 0-63), default 7 267 268 Don't forget that it's illegal to assign a channel to the same FX-bus accumulator 269 more than once (it means 0=0 && 1=0 is an invalid combination). 270 271 name='EMU10K1 PCM Send Volume',index 0-31 272 ----------------------------------------- 273 It specifies the attenuation (amount) for given destination in range 0-255. 274 The channel mapping is following: 275 276 * 0 - mono, A destination attn, default 255 (no attenuation) 277 * 1 - mono, B destination attn, default 255 (no attenuation) 278 * 2 - mono, C destination attn, default 0 (mute) 279 * 3 - mono, D destination attn, default 0 (mute) 280 * 4 - mono, E destination attn, default 0 (mute) 281 * 5 - mono, F destination attn, default 0 (mute) 282 * 6 - mono, G destination attn, default 0 (mute) 283 * 7 - mono, H destination attn, default 0 (mute) 284 * 8 - left, A destination attn, default 255 (no attenuation) 285 * 9 - left, B destination attn, default 0 (mute) 286 * 10 - left, C destination attn, default 0 (mute) 287 * 11 - left, D destination attn, default 0 (mute) 288 * 12 - left, E destination attn, default 0 (mute) 289 * 13 - left, F destination attn, default 0 (mute) 290 * 14 - left, G destination attn, default 0 (mute) 291 * 15 - left, H destination attn, default 0 (mute) 292 * 16 - right, A destination attn, default 0 (mute) 293 * 17 - right, B destination attn, default 255 (no attenuation) 294 * 18 - right, C destination attn, default 0 (mute) 295 * 19 - right, D destination attn, default 0 (mute) 296 * 20 - right, E destination attn, default 0 (mute) 297 * 21 - right, F destination attn, default 0 (mute) 298 * 22 - right, G destination attn, default 0 (mute) 299 * 23 - right, H destination attn, default 0 (mute) 300 301 302 303 MANUALS/PATENTS 304 =============== 305 306 See sb-live-mixer.rst.
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