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alsa-msp3410d - An alsa mixer driver for msp3410d sound processors
http://telin.rug.ac.be/~philips/alsa-msp3410d
Contents
What is alsa-msp3410d?
This is the very first version and probably also the very last
version of the code; I leave it here just in case somebody may find it
useful. If you are making available a new and better version of this
software on a website please let me know. I will then put a link on this
website.
alsa-msp3410d is a sound card driver for the MSP3410D chip
which is incorporated in many TV-cards such as the mirovideo pctv pro.
The driver is based on the Advanced
Linux Sound Architecture (ALSA) and works together with the bttv video
for linux driver for such cards. It compiles into a module snd-card-msp3410d
which implements a mixer driver.
alsa-msp3410d allows you to control the following features
of the MSP3410D chip through any alsa mixer (e.g., gamix or xamixer):
-
automatic volume correction:
-
bass and treble
-
five-band equalizer:
-
on/off switch (NOTE: if you switch on the equalizer, the
bass and treble controls are de-activated; this is how the chip works)
-
five band tone control
-
beeper inject: (probably pretty useless, but the register
was there so I couldn't leave it alone)
-
soft on/off switch
-
beeper volume
-
beeper frequency
-
3D effect:
-
soft on-off switch
-
SBE/SBE+PSE switch:
-
SBE: selects Stereo Baseline Enlargement only
-
SBE+PSE: selects atomatic switching between SBE and
Pseudo-stereo Effect depending on whether the source is mono or stereo
-
effect strength (can be negative or positive)
-
high pass gain for effect (in case manual high pass gain
is selected)
-
high pass auto gain switch: determines whether or not chip
selects
-
high-pass gain automatically or whether it uses the manual
value
-
Bass boost (loudness)
-
soft on/off switch
-
super boost switch (magnifies the effect)
-
loudness strength
-
Master volume
-
soft on/off switch (mutes/unmutes volume)
-
left and right volume
Supported operating systems
Only linux is supported. What else would you need?
Here is what it looks like in xamixer
What do you need?
-
A TV-card with an msp3410d or msp3400c (untested) chip on
it
-
bttv v4l-drivers.
Make sure you have a recent version of the driver and check that
the driver works before you attempt to make alsa-msp3410d work. Use bttv-0.7.52
if possible.
-
ALSA sound drivers.
Make sure alsa works before you attempt to try to make alsa-msp3410d work.
If you do not wish to use alsa for your PC's sound card, you can always
test with the alsa snd-card-dummy module. Use alsa-driver-0.5.10 if possible
-
an alsa mixer: gamix
or xamixer
(or ...). Currently, OSS-mixers do not work yet (this will be implemented
later)
Limitations
-
xamixer has an option for locking "left and right" volume
controls. If this option is on, the equaliser sliders are also locked together
which is pretty annoying
-
snd-card-msp3410d must be loaded AFTER the bttv modules
-
the bttv module msp3400 resets the chip whenever you change
channels; this means that all mixer settings are lost. It is possible to
fix this by applying the patch msp3400.c.patch to the bttv driver software.
-
programs such as xawtv directly change the volume (bypassing
the mixer) when they start.
Todo
-
Implement OSS-emulation code
-
Ask the Alsa-lib developers to implement an equalizer interface.
-
make a decent configure script
-
document the other stuff (e.g., mspproc)
Download
Friday, 09-Jan-2004 20:29:13 CET
