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Based on kernel version 3.16. Page generated on 2014-08-06 21:41 EST.

1	Support for the OPTi 82C931 chip
2	--------------------------------
3	Note: parts of this README file apply also to other
4	cards that use the mad16 driver.
5	
6	Some items in this README file are based on features
7	added to the sound driver after Linux-2.1.91 was out.
8	By the time of writing this I do not know which official
9	kernel release will include these features.
10	Please do not report inconsistencies on older Linux
11	kernels.
12	
13	The OPTi 82C931 is supported in its non-PnP mode.
14	Usually you do not need to set jumpers, etc. The sound driver
15	will check the card status and if it is required it will
16	force the card into a mode in which it can be programmed.
17	
18	If you have another OS installed on your computer it is recommended
19	that Linux and the other OS use the same resources.
20	
21	Also, it is recommended that resources specified in /etc/modprobe.d/*.conf
22	and resources specified in /etc/isapnp.conf agree.
23	
24	Compiling the sound driver
25	--------------------------
26	I highly recommend that you build a modularized sound driver.
27	This document does not cover a sound-driver which is built in
28	the kernel.
29	
30	Sound card support should be enabled as a module (chose m).
31	Answer 'm' for  these items:
32	  Generic OPL2/OPL3 FM synthesizer support		(CONFIG_SOUND_ADLIB)
33	  Microsoft Sound System support			(CONFIG_SOUND_MSS)
34	  Support for OPTi MAD16 and/or Mozart based cards	(CONFIG_SOUND_MAD16)
35	  FM synthesizer (YM3812/OPL-3) support			(CONFIG_SOUND_YM3812)
36	
37	The configuration menu may ask for addresses, IRQ lines or DMA
38	channels. If the card is used as a module the module loading
39	options will override these values.
40	
41	For the OPTi 931 you can answer 'n' to:
42	  Support MIDI in older MAD16 based cards (requires SB)	(CONFIG_SOUND_MAD16_OLDCARD)
43	If you do need MIDI support in a Mozart or C928 based card you
44	need to answer 'm' to the above question. In that case you will
45	also need to answer 'm' to:
46	  '100% Sound Blaster compatibles (SB16/32/64, ESS, Jazz16) support' (CONFIG_SOUND_SB)
47	
48	Go on and compile your kernel and modules. Install the modules. Run depmod -a.
49	
50	Using isapnptools
51	-----------------
52	In most systems with a PnP BIOS you do not need to use isapnp. The
53	initialization provided by the BIOS is sufficient for the driver
54	to pick up the card and continue initialization.
55	
56	If that fails, or if you have other PnP cards, you need to use isapnp
57	to initialize the card.
58	This was tested with isapnptools-1.11 but I recommend that you use
59	isapnptools-1.13 (or newer). Run pnpdump to dump the information
60	about your PnP cards. Then edit the resulting file and select
61	the options of your choice. This file is normally installed as
62	/etc/isapnp.conf.
63	
64	The driver has one limitation with respect to I/O port resources:
65	IO3 base must be 0x0E0C.  Although isapnp allows other ports, this
66	address is hard-coded into the driver.
67	
68	Using kmod and autoloading the sound driver
69	-------------------------------------------
70	Config files in '/etc/modprobe.d/' are used as below:
71	
72	alias mixer0 mad16
73	alias audio0 mad16
74	alias midi0  mad16
75	alias synth0 opl3
76	options sb mad16=1
77	options mad16 irq=10 dma=0 dma16=1 io=0x530 joystick=1 cdtype=0
78	options opl3 io=0x388
79	install mad16 /sbin/modprobe -i mad16 && /sbin/ad1848_mixer_reroute 14 8 15 3 16 6
80	
81	If you have an MPU daughtercard or onboard MPU you will want to add to the
82	"options mad16" line - eg 
83	
84	options mad16 irq=5 dma=0 dma16=3 io=0x530 mpu_io=0x330 mpu_irq=9
85	
86	To set the I/O and IRQ of the MPU.
87	
88	
89	Explain:
90	
91	alias mixer0 mad16
92	alias audio0 mad16
93	alias midi0  mad16
94	alias synth0 opl3
95	
96	When any sound device is opened the kernel requests auto-loading
97	of char-major-14. There is a built-in alias that translates this
98	request to loading the main sound module.
99	
100	The sound module in its turn will request loading of a sub-driver
101	for mixer, audio, midi or synthesizer device. The first 3 are
102	supported by the mad16 driver. The synth device is supported
103	by the opl3 driver.
104	
105	There is currently no way to autoload the sound device driver
106	if more than one card is installed.
107	
108	options sb mad16=1
109	
110	This is left for historical reasons. If you enable the
111	config option 'Support MIDI in older MAD16 based cards (requires SB)'
112	or if you use an older mad16 driver it will force loading of the
113	SoundBlaster driver. This option tells the SB driver not to look
114	for a SB card but to wait for the mad16 driver.
115	
116	options mad16 irq=10 dma=0 dma16=1 io=0x530 joystick=1 cdtype=0
117	options opl3 io=0x388
118	
119	post-install mad16 /sbin/ad1848_mixer_reroute 14 8 15 3 16 6
120	
121	This sets resources and options for the mad16 and opl3 drivers.
122	I use two DMA channels (only one is required) to enable full duplex.
123	joystick=1 enables the joystick port. cdtype=0 disables the cd port.
124	You can also set mpu_io and mpu_irq in the mad16 options for the
125	uart401 driver.
126	
127	This tells modprobe to run /sbin/ad1848_mixer_reroute after
128	mad16 is successfully loaded and initialized. The source
129	for ad1848_mixer_reroute is appended to the end of this readme
130	file. It is impossible for the sound driver to know the actual
131	connections to the mixer. The 3 inputs intended for cd, synth
132	and line-in are mapped to the generic inputs line1, line2 and
133	line3. This program reroutes these mixer channels to their
134	right names (note the right mapping depends on the actual sound
135	card that you use).
136	The numeric parameters mean:
137	 14=line1 8=cd    - reroute line1 to the CD input.
138	 15=line2 3=synth - reroute line2 to the synthesizer input.
139	 16=line3 6=line  - reroute line3 to the line input.
140	For reference on other input names look at the file
141	/usr/include/linux/soundcard.h.
142	
143	Using a joystick
144	-----------------
145	You must enable a joystick in the mad16 options. (also
146	in /etc/isapnp.conf if you use it).
147	Tested with regular analog joysticks.
148	
149	A CDROM drive connected to the sound card
150	-----------------------------------------
151	The 82C931 chip has support only for secondary ATAPI cdrom.
152	(cdtype=8). Loading the mad16 driver resets the C931 chip
153	and if a cdrom was already mounted it may cause a complete
154	system hang. Do not use the sound card if you have an alternative.
155	If you do use the sound card it is important that you load
156	the mad16 driver (use "modprobe mad16" to prevent auto-unloading)
157	before the cdrom is accessed the first time.
158	
159	Using the sound driver built-in to the kernel may help here, but...
160	Most new systems have a PnP BIOS and also two IDE controllers.
161	The IDE controller on the sound card may be needed only on older
162	systems (which have only one IDE controller) but these systems
163	also do not have a PnP BIOS - requiring isapnptools and a modularized
164	driver.
165	
166	Known problems
167	--------------
168	1. See the section on "A CDROM drive connected to the sound card".
169	
170	2. On my system the codec cannot capture companded sound samples.
171	   (eg., recording from /dev/audio). When any companded capture is
172	   requested I get stereo-16 bit samples instead. Playback of
173	   companded samples works well. Apparently this problem is not common
174	   to all C931 based cards. I do not know how to identify cards that
175	   have this problem.
176	
177	Source for ad1848_mixer_reroute.c
178	---------------------------------
179	#include <stdio.h>
180	#include <fcntl.h>
181	#include <linux/soundcard.h>
182	
183	static char *mixer_names[SOUND_MIXER_NRDEVICES] =
184		SOUND_DEVICE_LABELS;
185	
186	int
187	main(int argc, char **argv) {
188		int val, from, to;
189		int i, fd;
190	
191		fd = open("/dev/mixer", O_RDWR);
192		if(fd < 0) {
193			perror("/dev/mixer");
194			return 1;
195		}
196	
197		for(i = 2; i < argc; i += 2) {
198			from = atoi(argv[i-1]);
199			to = atoi(argv[i]);
200	
201			if(to == SOUND_MIXER_NONE)
202				fprintf(stderr, "%s: turning off mixer %s\n",
203					argv[0], mixer_names[to]);
204			else
205				fprintf(stderr, "%s: rerouting mixer %s to %s\n",
206					argv[0], mixer_names[from], mixer_names[to]);
207	
208			val = from << 8 | to;
209	
210			if(ioctl(fd, SOUND_MIXER_PRIVATE2, &val)) {
211				perror("AD1848 mixer reroute");
212				return 1;
213			}
214		}
215	
216		return 0;
217	}
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