Penguin

Differences between current version and predecessor to the previous major change of TvTunerCards.

Other diffs: Previous Revision, Previous Author, or view the Annotated Edit History

Newer page: version 21 Last edited on Wednesday, April 12, 2006 7:52:18 pm by DouglasBagnall
Older page: version 19 Last edited on Monday, February 20, 2006 11:49:51 am by FabienOrjollet Revert
@@ -42,16 +42,18 @@
 Note that this card also has a RadioTuner in it - see that page for setup hints. 
  
 Support is in the mainstream 2.6 kernel. If you use a 2.4 series kernel you will need to download drivers and a few small kernel patches from http://bytesex.org/saa7134/. You will need to be using kernel 2.4.20 or later to apply these patches - the kernel patches use [V4L] ([Video4Linux]) version 2, while the 2.4 series kernels use version 1). 
  
-You still need to configure I2C support in the kernel as above,  
- as well as making a module for saa7134 ("Device Drivers -> Multimedia devices -> Video For Linux -> Philips SAA7134 support"). 
+You still need to configure I2C support in the kernel as for BT8x8  
+ above, as well as making a module for saa7134 ("Device Drivers ->  
+ Multimedia devices -> Video For Linux -> Philips SAA7134 support"). 
 If you can "modprobe saa7134" then your kernel already has this 
-module. 
+module. IN 2.6.16, extra sound support has been split off into  
+additional modules, saa7134-alsa and (apparently) saa7134-oss. You  
+don't need these to just watch TV. See the sound section below
  
 Here a some gotchas I noticed (for the New Zealand version of this board, at least): 
 # I needed to add "oss=1" as a option for the saa7134 module to get any sound. I guess it was defaulting to alsa, but this option wasn't mentioned anywhere - I found it accidentally when doing modinfo(8). 
-# Audio is handled by a small loop-back cable, out of the tuner card going back into the "line in" on the sound card. (Don't forget to adjust the volume for "line in" in your favourite sound mixer/volume control.)  
 # The default tuner type for the card was wrong. In New Zealand we use PAL BG (or compatible), and it was defaulting to some other tuner type which meant I could pick up UHF but not VHF channels. (See the notes below about tuner type). 
  
 Here is the relevant snippet from my /etc/modules.conf (for 2.4 kernels, or /etc/modprobe.d/tv for 2.6 kernels): 
 <verbatim> 
@@ -146,8 +148,47 @@
 and comment out or remove the two lines: 
  printk("%s: build_key gpio=0x%x mask=0x%x data=%d\n", 
  dev->name, gpio, ir->mask_keycode, data); 
 and re-compile the module or your kernel. (This worked for kernel 2.6.4 at least.) 
+  
+!!Sound  
+  
+Saa7134 boards always seem to come with a small loop-back cable to  
+connect with the "line in" of your sound card. This is the simplest  
+way to get sound, and is presumably what Windows does, but it is not  
+actually necessary with recent kernels.  
+  
+!External loopback sound  
+  
+ If you use the loop-back cable, all you need to do is adjust the  
+volume for "line in" in your favourite sound mixer/volume control.  
+The TV card spits out audio whenever the tuner is used -- your video  
+application doesn't need to know about it.  
+  
+!DMA sound access  
+  
+If you want to use your line in for something else, or want to process  
+the sound and video together, you can access the sound chip on the  
+tuner card directly. With 2.6.16, you can go something like:  
+  
+<verbatim>  
+$ sudo modprobe saa7134-alsa  
+  
+$ mplayer tv:// -tv driver=v4l2:input=0:width=384:height=288:adevice=hw.1,0:\  
+audiorate=32000:forceaudio:volume=100:alsa:immediatemode=0  
+</verbatim>  
+  
+for DMA access. The <tt>audiorate=32000</tt> is vital; saa7134 only  
+does 32k sound. <tt>forceaudio</tt> and <tt>immediatemode=0</tt> tell  
+mplayer not to be lazy -- by default it will assume you are using the  
+loop-back. The numbers in <tt>adevice=hw.1,0</tt> depend on your  
+actual hardware. You can also leave out the <tt>alsa</tt> and use  
+<tt>adevice=/dev/dsp1</tt> -- oss emulation ought to take care of it.  
+  
+The source for this kind of thing is of course the  
+[v4l wiki|http://www.linuxtv.org/v4lwiki/index.php/Saa7134-alsa].  
+  
+  
  
 !!Tuner type 
 Some cards have an [EEPROM] on them which means that your OperatingSystem can automatically figure out what type of tuner chip it is using. Some cards -- especially the cheaper ones -- save a few cents per card by not putting this on, and hard-code the tuner-type into the driver. This works on windows if they give you a CDROM with binary drivers on it, but doesn't work so well 
 if you use drivers that come from anywhere else.