'Splain please re: mixer, alsa, pulseaudio and tvtime??

[Michael Schwendt]

On Fri, 24 Jul 2009 16:20:36 -0400, William wrote:

> >   sudo alsa-info --no-upload --with-amixer --with-devices

So, your onboard audio chipset is ALSA device '0', and the TV card does
not appear as a second audio device '1'. That can be helpful, because lots
of other tv/radio cards appears as a seperate audio device and add several
playback/capture controls to ALSA based tools and applications.
Confusing, however, is to see not only a pair of digital+analogue capture
hw devices but a second analogue one. Settings are only provided for
two though, and the 2nd one is switched off.

[same as $ amixer get 'Capture',0 ]         # 'name',index
Simple mixer control 'Capture',0
  Capabilities: cvolume cswitch
  Capture channels: Front Left - Front Right
  Limits: Capture 0 - 31
  Front Left: Capture 31 [100%] [34.50dB] [on]
  Front Right: Capture 31 [100%] [34.50dB] [on]

[ $ amixer get 'Capture',1 ]
Simple mixer control 'Capture',1
  Capabilities: cvolume cswitch
  Capture channels: Front Left - Front Right
  Limits: Capture 0 - 31
  Front Left: Capture 17 [55%] [13.50dB] [off]
  Front Right: Capture 17 [55%] [13.50dB] [off]

Simple mixer control 'Input Source',0
  Capabilities: cenum
  Items: 'Mic' 'Front Mic' 'Line' 'CD'
  Item0: 'Line'

Simple mixer control 'Input Source',1
  Capabilities: cenum
  Items: 'Mic' 'Front Mic' 'Line' 'CD'
  Item0: 'Mic'

> > ? ALSA numbers the audio devices it finds, starting with 0. (That's the
> > name N number you can pass to alsamixer -cN when using it as an alternative
> > to tvtime's mixer functionality.)
> > 
> Yes, but are the audio devices in the /proc, /dev, or /sys vfs.  If so,
> where? 

ALSA enumerates the hardware devices. The Linux device files are in
/dev/snd/ with ALSA giving info in /proc/asound/, but you still need to
contruct intentifiers as understood by amixer, too. While you only have
one 'Line' (or 'Line',0) you have 'Capture',0 and 'Capture',1, and
when switching on your tv card using Linux, it must be clear how
audio is routed (if at all) or whether the only available way is to
decode and play back the mpeg stream on /dev/video1.

> ...
> cx23885 driver version 0.0.1 loaded
> cx23885 0000:02:00.0: PCI INT A -> GSI 16 (level, low) -> IRQ 16
> CORE cx23885[0]: subsystem: 0070:7801, board: Hauppauge WinTV-HVR1800
> [card=2,autodetected]
> tveeprom 1-0050: Hauppauge model 78521, rev C1E9, serial# 4870798
> tveeprom 1-0050: MAC address is 00-0D-FE-4A-52-8E
> tveeprom 1-0050: tuner model is Philips 18271_8295 (idx 149, type 54)
> tveeprom 1-0050: TV standards NTSC(M) ATSC/DVB Digital (eeprom 0x88)
> tveeprom 1-0050: audio processor is CX23887 (idx 42)
> tveeprom 1-0050: decoder processor is CX23887 (idx 37)
> tveeprom 1-0050: has radio
> cx23885[0]: hauppauge eeprom: model=78521
> cx25840 3-0044: cx25  0-21 found @ 0x88 (cx23885[0])
> cx25840 3-0044: firmware: requesting v4l-cx23885-avcore-01.fw
> cx25840 3-0044: unable to open firmware v4l-cx23885-avcore-01.fw

Firmware file isn't found:
http://www.linuxtv.org/wiki/index.php/Hauppauge_WinTV-HVR-1800#Firmware

> The above site suggests the addition of firmware for cx23885
> The 2.6.29.6-213.fc11.x86_64 kernel seems to have that module included.

I may misunderstand you, but "module" and "firmware" are two different
things. The Linux kernel includes the driver, the "kernel module", but
that module still sends a request to load a separate firmware file. I
cannot spot that file in the kernel-firmware package either.

> >  for /dev/video0 (as only
> > the channel chooser) and 
> 
> > mplayer for playing the mpeg stream on
> > /dev/video1?
> 
> I haven't gone back to mplayer.  I originally tried it as an experiment,
> in the hopes to learn something about tv tuners etc. and why tvtime
> wasn't working.  I am not sure it is a worthwhile experiment, but will
> try to get mplayer going, if you suggest it.

That is because the few success reports mention that as a solution.