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Documentation / sound / alsa / Audigy-mixer.txt




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Based on kernel version 3.15.4. Page generated on 2014-07-07 09:04 EST.

1	
2			Sound Blaster Audigy mixer / default DSP code
3			===========================================
4	
5	This is based on SB-Live-mixer.txt.
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	1) Digital mixer controls
17	-------------------------
18	
19	These controls are built using the DSP instructions. They offer extended
20	functionality. Only the default build-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 wrapped 
24	(set to maximal or minimal value without checking of overflow).
25	
26	
27	Explanation of used abbreviations:
28	
29	DAC    - digital to analog converter
30	ADC    - analog to digital converter
31	I2S    - one-way three wire serial bus for digital sound by Philips Semiconductors
32	         (this standard is used for connecting standalone DAC and ADC converters)
33	LFE    - low frequency effects (subwoofer signal)
34	AC97   - a chip containing an analog mixer, DAC and ADC converters
35	IEC958 - S/PDIF
36	FX-bus - the EMU10K2 chip has an effect bus containing 64 accumulators.
37	         Each of the synthesizer voices can feed its output to these accumulators
38	         and the DSP microcontroller can operate with the resulting sum.
39	
40	name='PCM Front Playback Volume',index=0
41	
42	This control is used to attenuate samples for left and right front PCM FX-bus
43	accumulators. ALSA uses accumulators 8 and 9 for left and right front PCM 
44	samples for 5.1 playback. The result samples are forwarded to the front DAC PCM 
45	slots of the Philips DAC.
46	
47	name='PCM Surround Playback Volume',index=0
48	
49	This control is used to attenuate samples for left and right surround PCM FX-bus
50	accumulators. ALSA uses accumulators 2 and 3 for left and right surround PCM 
51	samples for 5.1 playback. The result samples are forwarded to the surround DAC PCM 
52	slots of the Philips DAC.
53	
54	name='PCM Center Playback Volume',index=0
55	
56	This control is used to attenuate samples for center PCM FX-bus accumulator.
57	ALSA uses accumulator 6 for center PCM sample for 5.1 playback. The result sample
58	is forwarded to the center DAC PCM slot of the Philips DAC.
59	
60	name='PCM LFE Playback Volume',index=0
61	
62	This control is used to attenuate sample for LFE PCM FX-bus accumulator. 
63	ALSA uses accumulator 7 for LFE PCM sample for 5.1 playback. The result sample 
64	is forwarded to the LFE DAC PCM slot of the Philips DAC.
65	
66	name='PCM Playback Volume',index=0
67	
68	This control is used to attenuate samples for left and right PCM FX-bus
69	accumulators. ALSA uses accumulators 0 and 1 for left and right PCM samples for
70	stereo playback. The result samples are forwarded to the front DAC PCM slots 
71	of the Philips DAC.
72	
73	name='PCM Capture Volume',index=0
74	
75	This control is used to attenuate samples for left and right PCM FX-bus
76	accumulator. ALSA uses accumulators 0 and 1 for left and right PCM.
77	The result is forwarded to the ADC capture FIFO (thus to the standard capture
78	PCM device).
79	
80	name='Music Playback Volume',index=0
81	
82	This control is used to attenuate samples for left and right MIDI FX-bus
83	accumulators. ALSA uses accumulators 4 and 5 for left and right MIDI samples.
84	The result samples are forwarded to the front DAC PCM slots of the AC97 codec.
85	
86	name='Music Capture Volume',index=0
87	
88	These controls are used to attenuate samples for left and right MIDI FX-bus
89	accumulator. ALSA uses accumulators 4 and 5 for left and right PCM.
90	The result is forwarded to the ADC capture FIFO (thus to the standard capture
91	PCM device).
92	
93	name='Mic Playback Volume',index=0
94	
95	This control is used to attenuate samples for left and right Mic input.
96	For Mic input is used AC97 codec. The result samples are forwarded to 
97	the front DAC PCM slots of the Philips DAC. Samples are forwarded to Mic
98	capture FIFO (device 1 - 16bit/8KHz mono) too without volume control.
99	
100	name='Mic Capture Volume',index=0
101	
102	This control is used to attenuate samples for left and right Mic input.
103	The result is forwarded to the ADC capture FIFO (thus to the standard capture
104	PCM device).
105	
106	name='Audigy CD Playback Volume',index=0
107	
108	This control is used to attenuate samples from left and right IEC958 TTL
109	digital inputs (usually used by a CDROM drive). The result samples are
110	forwarded to the front DAC PCM slots of the Philips DAC.
111	
112	name='Audigy CD Capture Volume',index=0
113	
114	This control is used to attenuate samples from left and right IEC958 TTL
115	digital inputs (usually used by a CDROM drive). The result samples are
116	forwarded to the ADC capture FIFO (thus to the standard capture PCM device).
117	
118	name='IEC958 Optical Playback Volume',index=0
119	
120	This control is used to attenuate samples from left and right IEC958 optical
121	digital input. The result samples are forwarded to the front DAC PCM slots
122	of the Philips DAC.
123	
124	name='IEC958 Optical Capture Volume',index=0
125	
126	This control is used to attenuate samples from left and right IEC958 optical
127	digital inputs. The result samples are forwarded to the ADC capture FIFO
128	(thus to the standard capture PCM device).
129	
130	name='Line2 Playback Volume',index=0
131	
132	This control is used to attenuate samples from left and right I2S ADC
133	inputs (on the AudigyDrive). The result samples are forwarded to the front
134	DAC PCM slots of the Philips DAC.
135	
136	name='Line2 Capture Volume',index=1
137	
138	This control is used to attenuate samples from left and right I2S ADC
139	inputs (on the AudigyDrive). The result samples are forwarded to the ADC
140	capture FIFO (thus to the standard capture PCM device).
141	
142	name='Analog Mix Playback Volume',index=0
143	
144	This control is used to attenuate samples from left and right I2S ADC
145	inputs from Philips ADC. The result samples are forwarded to the front
146	DAC PCM slots of the Philips DAC. This contains mix from analog sources
147	like CD, Line In, Aux, ....
148	
149	name='Analog Mix Capture Volume',index=1
150	
151	This control is used to attenuate samples from left and right I2S ADC
152	inputs Philips ADC. The result samples are forwarded to the ADC
153	capture FIFO (thus to the standard capture PCM device).
154	
155	name='Aux2 Playback Volume',index=0
156	
157	This control is used to attenuate samples from left and right I2S ADC
158	inputs (on the AudigyDrive). The result samples are forwarded to the front
159	DAC PCM slots of the Philips DAC.
160	
161	name='Aux2 Capture Volume',index=1
162	
163	This control is used to attenuate samples from left and right I2S ADC
164	inputs (on the AudigyDrive). The result samples are forwarded to the ADC
165	capture FIFO (thus to the standard capture PCM device).
166	
167	name='Front Playback Volume',index=0
168	
169	All stereo signals are mixed together and mirrored to surround, center and LFE.
170	This control is used to attenuate samples for left and right front speakers of
171	this mix.
172	
173	name='Surround Playback Volume',index=0
174	
175	All stereo signals are mixed together and mirrored to surround, center and LFE.
176	This control is used to attenuate samples for left and right surround speakers of
177	this mix.
178	
179	name='Center Playback Volume',index=0
180	
181	All stereo signals are mixed together and mirrored to surround, center and LFE.
182	This control is used to attenuate sample for center speaker of this mix.
183	
184	name='LFE Playback Volume',index=0
185	
186	All stereo signals are mixed together and mirrored to surround, center and LFE.
187	This control is used to attenuate sample for LFE speaker of this mix.
188	
189	name='Tone Control - Switch',index=0
190	
191	This control turns the tone control on or off. The samples for front, rear
192	and center / LFE outputs are affected.
193	
194	name='Tone Control - Bass',index=0
195	
196	This control sets the bass intensity. There is no neutral value!!
197	When the tone control code is activated, the samples are always modified.
198	The closest value to pure signal is 20.
199	
200	name='Tone Control - Treble',index=0
201	
202	This control sets the treble intensity. There is no neutral value!!
203	When the tone control code is activated, the samples are always modified.
204	The closest value to pure signal is 20.
205	
206	name='Master Playback Volume',index=0
207	
208	This control is used to attenuate samples for front, surround, center and 
209	LFE outputs.
210	
211	name='IEC958 Optical Raw Playback Switch',index=0
212	
213	If this switch is on, then the samples for the IEC958 (S/PDIF) digital
214	output are taken only from the raw FX8010 PCM, otherwise standard front
215	PCM samples are taken.
216	
217	
218	2) PCM stream related controls
219	------------------------------
220	
221	name='EMU10K1 PCM Volume',index 0-31
222	
223	Channel volume attenuation in range 0-0xffff. The maximum value (no
224	attenuation) is default. The channel mapping for three values is
225	as follows:
226	
227		0 - mono, default 0xffff (no attenuation)
228		1 - left, default 0xffff (no attenuation)
229		2 - right, default 0xffff (no attenuation)
230	
231	name='EMU10K1 PCM Send Routing',index 0-31
232	
233	This control specifies the destination - FX-bus accumulators. There 24
234	values with this mapping:
235	
236		 0 -  mono, A destination (FX-bus 0-63), default 0
237		 1 -  mono, B destination (FX-bus 0-63), default 1
238		 2 -  mono, C destination (FX-bus 0-63), default 2
239		 3 -  mono, D destination (FX-bus 0-63), default 3
240		 4 -  mono, E destination (FX-bus 0-63), default 0
241		 5 -  mono, F destination (FX-bus 0-63), default 0
242		 6 -  mono, G destination (FX-bus 0-63), default 0
243		 7 -  mono, H destination (FX-bus 0-63), default 0
244		 8 -  left, A destination (FX-bus 0-63), default 0
245		 9 -  left, B destination (FX-bus 0-63), default 1
246		10 -  left, C destination (FX-bus 0-63), default 2
247		11 -  left, D destination (FX-bus 0-63), default 3
248		12 -  left, E destination (FX-bus 0-63), default 0
249		13 -  left, F destination (FX-bus 0-63), default 0
250		14 -  left, G destination (FX-bus 0-63), default 0
251		15 -  left, H destination (FX-bus 0-63), default 0
252		16 - right, A destination (FX-bus 0-63), default 0
253		17 - right, B destination (FX-bus 0-63), default 1
254		18 - right, C destination (FX-bus 0-63), default 2
255		19 - right, D destination (FX-bus 0-63), default 3
256		20 - right, E destination (FX-bus 0-63), default 0
257		21 - right, F destination (FX-bus 0-63), default 0
258		22 - right, G destination (FX-bus 0-63), default 0
259		23 - right, H destination (FX-bus 0-63), default 0
260	
261	Don't forget that it's illegal to assign a channel to the same FX-bus accumulator 
262	more than once (it means 0=0 && 1=0 is an invalid combination).
263	 
264	name='EMU10K1 PCM Send Volume',index 0-31
265	
266	It specifies the attenuation (amount) for given destination in range 0-255.
267	The channel mapping is following:
268	
269		 0 -  mono, A destination attn, default 255 (no attenuation)
270		 1 -  mono, B destination attn, default 255 (no attenuation)
271		 2 -  mono, C destination attn, default 0 (mute)
272		 3 -  mono, D destination attn, default 0 (mute)
273		 4 -  mono, E destination attn, default 0 (mute)
274		 5 -  mono, F destination attn, default 0 (mute)
275		 6 -  mono, G destination attn, default 0 (mute)
276		 7 -  mono, H destination attn, default 0 (mute)
277		 8 -  left, A destination attn, default 255 (no attenuation)
278		 9 -  left, B destination attn, default 0 (mute)
279		10 -  left, C destination attn, default 0 (mute)
280		11 -  left, D destination attn, default 0 (mute)
281		12 -  left, E destination attn, default 0 (mute)
282		13 -  left, F destination attn, default 0 (mute)
283		14 -  left, G destination attn, default 0 (mute)
284		15 -  left, H destination attn, default 0 (mute)
285		16 - right, A destination attn, default 0 (mute)
286		17 - right, B destination attn, default 255 (no attenuation)
287		18 - right, C destination attn, default 0 (mute)
288		19 - right, D destination attn, default 0 (mute)
289		20 - right, E destination attn, default 0 (mute)
290		21 - right, F destination attn, default 0 (mute)
291		22 - right, G destination attn, default 0 (mute)
292		23 - right, H destination attn, default 0 (mute)
293	
294	
295	
296	4) MANUALS/PATENTS:
297	-------------------
298	
299	ftp://opensource.creative.com/pub/doc
300	-------------------------------------
301	
302	        Files:
303	        LM4545.pdf      AC97 Codec
304	
305	        m2049.pdf       The EMU10K1 Digital Audio Processor
306	
307	        hog63.ps        FX8010 - A DSP Chip Architecture for Audio Effects
308	
309	
310	WIPO Patents
311	------------
312	        Patent numbers:
313	        WO 9901813 (A1) Audio Effects Processor with multiple asynchronous (Jan. 14, 1999)
314	                        streams
315	
316	        WO 9901814 (A1) Processor with Instruction Set for Audio Effects (Jan. 14, 1999)
317	
318	        WO 9901953 (A1) Audio Effects Processor having Decoupled Instruction
319	                        Execution and Audio Data Sequencing (Jan. 14, 1999)
320	
321	
322	US Patents (http://www.uspto.gov/)
323	----------------------------------
324	
325	        US 5925841      Digital Sampling Instrument employing cache memory (Jul. 20, 1999)
326	
327	        US 5928342      Audio Effects Processor integrated on a single chip (Jul. 27, 1999)
328	                        with a multiport memory onto which multiple asynchronous
329	                        digital sound samples can be concurrently loaded
330	
331	        US 5930158      Processor with Instruction Set for Audio Effects (Jul. 27, 1999)
332	
333	        US 6032235      Memory initialization circuit (Tram) (Feb. 29, 2000)
334	
335	        US 6138207      Interpolation looping of audio samples in cache connected to    (Oct. 24, 2000)
336	                        system bus with prioritization and modification of bus transfers
337	                        in accordance with loop ends and minimum block sizes
338	
339	        US 6151670      Method for conserving memory storage using a (Nov. 21, 2000)
340	                        pool of  short term memory registers
341	
342	        US 6195715      Interrupt control for multiple programs communicating with      (Feb. 27, 2001)
343	                        a common interrupt by associating programs to GP registers,
344	                        defining interrupt register, polling GP registers, and invoking
345	                        callback routine associated with defined interrupt register
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