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Documentation / sound / alsa / MIXART.txt


Based on kernel version 4.9. Page generated on 2016-12-21 14:37 EST.

1	    Alsa driver for Digigram miXart8 and miXart8AES/EBU soundcards
2		    Digigram <alsa@digigram.com>
3	
4	
5	GENERAL
6	=======
7	
8	The miXart8 is a multichannel audio processing and mixing soundcard
9	that has 4 stereo audio inputs and 4 stereo audio outputs.
10	The miXart8AES/EBU is the same with a add-on card that offers further
11	4 digital stereo audio inputs and outputs.
12	Furthermore the add-on card offers external clock synchronisation
13	(AES/EBU, Word Clock, Time Code and Video Synchro)
14	
15	The mainboard has a PowerPC that offers onboard mpeg encoding and
16	decoding, samplerate conversions and various effects.
17	
18	The driver don't work properly at all until the certain firmwares
19	are loaded, i.e. no PCM nor mixer devices will appear.
20	Use the mixartloader that can be found in the alsa-tools package.
21	
22	
23	VERSION 0.1.0
24	=============
25	
26	One miXart8 board will be represented as 4 alsa cards, each with 1
27	stereo analog capture 'pcm0c' and 1 stereo analog playback 'pcm0p' device.
28	With a miXart8AES/EBU there is in addition 1 stereo digital input
29	'pcm1c' and 1 stereo digital output 'pcm1p' per card.
30	
31	Formats
32	-------
33	U8, S16_LE, S16_BE, S24_3LE, S24_3BE, FLOAT_LE, FLOAT_BE
34	Sample rates : 8000 - 48000 Hz continuously
35	
36	Playback
37	--------
38	For instance the playback devices are configured to have max. 4
39	substreams performing hardware mixing. This could be changed to a
40	maximum of 24 substreams if wished.
41	Mono files will be played on the left and right channel. Each channel
42	can be muted for each stream to use 8 analog/digital outputs separately.
43	
44	Capture
45	-------
46	There is one substream per capture device. For instance only stereo
47	formats are supported.
48	
49	Mixer
50	-----
51	<Master> and <Master Capture> : analog volume control of playback and capture PCM.
52	<PCM 0-3> and <PCM Capture> : digital volume control of each analog substream.
53	<AES 0-3> and <AES Capture> : digital volume control of each AES/EBU substream.
54	<Monitoring> : Loopback from 'pcm0c' to 'pcm0p' with digital volume
55	and mute control.
56	
57	Rem : for best audio quality try to keep a 0 attenuation on the PCM
58	and AES volume controls which is set by 219 in the range from 0 to 255
59	(about 86% with alsamixer)
60	
61	
62	NOT YET IMPLEMENTED
63	===================
64	
65	- external clock support (AES/EBU, Word Clock, Time Code, Video Sync)
66	- MPEG audio formats
67	- mono record
68	- on-board effects and samplerate conversions
69	- linked streams
70	
71	
72	FIRMWARE
73	========
74	
75	[As of 2.6.11, the firmware can be loaded automatically with hotplug
76	 when CONFIG_FW_LOADER is set.  The mixartloader is necessary only
77	 for older versions or when you build the driver into kernel.]
78	 
79	For loading the firmware automatically after the module is loaded, use a
80	install command.  For example, add the following entry to
81	/etc/modprobe.d/mixart.conf for miXart driver:
82	
83		install snd-mixart /sbin/modprobe --first-time -i snd-mixart && \
84				   /usr/bin/mixartloader
85	(for 2.2/2.4 kernels, add "post-install snd-mixart /usr/bin/vxloader" to
86	 /etc/modules.conf, instead.)
87	
88	The firmware binaries are installed on /usr/share/alsa/firmware
89	(or /usr/local/share/alsa/firmware, depending to the prefix option of
90	configure).  There will be a miXart.conf file, which define the dsp image
91	files.
92	
93	The firmware files are copyright by Digigram SA
94	
95	
96	COPYRIGHT
97	=========
98	
99	Copyright (c) 2003 Digigram SA <alsa@digigram.com>
100	Distributable under GPL.
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