
IMPORTANT:  Don't send me mails with images attached unless I ask you
to do so.  Mails with images attached will go to /dev/null unseen.


Release notes for bttv-0.7.x
============================

This version is based on Ralphs 0.6.4 release.  There are alot of
changes.  Bugfixes, merged patches from other people, merged fixes
from the kernel version, port to the new i2c stack, removed support
for 2.0.x, code cleanups, ...

To compile this bttv version, you'll the new i2c stack.  Kernels
newer than 2.3.34 have this already included.  If you have a older
kernel, download it from:
	http://www2.lm-sensors.nu/~lm78/download.html

You'll need at least these config options for bttv:
CONFIG_I2C=m
CONFIG_I2C_ALGOBIT=m
CONFIG_VIDEO_DEV=m

The latest bttv version is available from http://bytesex.org/bttv/

You'll find Ralphs original (mostly outdated) documentation in the
ralphs-doc subdirectory.


Compile bttv
------------

If you are compiling the kernel version, just say 'm' if you are asked
for bttv.  I /strongly/ recommend to compile bttv as module, because
there are some insmod options for configuring the driver.  Starting
with 0.7.49 the most important ones are available as kernel args too.

If you downloaded the separate bttv bundle:  You need configured kernel
sources to compile the bttv driver.  The driver uses some Makefile
magic to compile the modules with your kernel's configuration
(wrt. module-versions, SMP, ...).  If you already have compiled the
kernel at least once, you probably don't have do worry about this.  If
not, go to /usr/src/linux and run at least "make config".  Even
better, compile your own kernel, you'll never become a real hacker
else ;-)
Note that you have to turn on video4linux support (CONFIG_VIDEO_DEV)
in the kernel to get the videodev.o module which is required by bttv.


Make bttv work with your card
-----------------------------

Setup your /etc/modules.conf file and let kmod load the modules.
See also:

Modules.conf:	some sample entries for /etc/modules.conf
Insmod-options:	list of all insmod options available for bttv and
		the helper modules.
MAKEDEV:	a script to create the special files for v4l
CARDLIST:	List of all supported cards
Cards:		more detailed descriptions of known TV cards:
		OEM name variants, used i2c chips, ...
		also includes non-bttv cards.

Loading just the bttv modules isn't enouth for most cards.  The
drivers for the i2c tuner/sound chips must also be loaded.  bttv tries
to load them automagically by calling request_module() now, but this
obviously works only with kmod enabled.

If bttv takes very long to load (happens sometimes with the cheap
cards which have no tuner), try adding this to your modules.conf:
	options i2c-algo-bit bit_test=1

The most important insmod option for bttv is "card=n" to select the
correct card type in case the autodetection does'nt work. If you get
video but no sound you've very likely specified the wrong (or no)
card type.  A list of supported cards is in CARDLIST.

If your card isn't listed in CARDLIST or if you have trouble making
audio work, you should read the Sound-FAQ.


Autodetecting cards
-------------------

bttv uses the PCI Subsystem ID to autodetect the card type.  lspci lists
the Subsystem ID in the second line, looks like this:

00:0a.0 Multimedia video controller: Brooktree Corporation Bt878 (rev 02)
        Subsystem: Hauppauge computer works Inc. WinTV/GO
        Flags: bus master, medium devsel, latency 32, IRQ 5
        Memory at e2000000 (32-bit, prefetchable) [size=4K]

only bt878-based cards can have a subsystem ID (which does not mean
that every card really has one).  bt848 cards can't have a Subsystem
ID and therefore can't be autodetected.  There is a list with the ID's
in bttv-cards.c (in case you are intrested or want to mail patches
with updates).

Old driver versions used to have a heuristic which could identify some
bt848-based cards.  It worked for Hauppauge and Miro cards in most
cases (simply because these where the first cards available on the
market), but misdetected other bt848 cards.  That code is gone now for
exactly this reason, the misdetection confused lots of people.  If you
have a old Hauppauge or Miro card, you'll have to load the driver with
card=1 or card=2 these days.


Still doesn't work?
-------------------

I do NOT have a lab with 30+ different grabber boards and a
PAL/NTSC/SECAM test signal generator at home, so I often can't
reproduce your problems.  This makes debugging very difficult for me.
If you have some knowledge and spare time, please try to fix this
yourself (patches very welcome of course...)  You know: The linux
slogan is "Do it yourself".

There is a mailing list: video4linux-list@redhat.com.
https://listman.redhat.com/mailman/listinfo/video4linux-list

If you have trouble with some specific TV card, try to ask there
instead of mailing me directly.  The chance that someone with the
same card listens there is much higher...

For problems with sound:  There are alot of different systems used
for TV sound all over the world.  And there are also different chips
which decode the audio signal.  Reports about sound problems ("stereo
does'nt work") are pretty useless unless you include some details
about your hardware and the TV sound scheme used in your country (or
at least the country you are living in).


Finally: If you mail some patches for bttv around the world (to
linux-kernel/Alan/Linus/...), please Cc: me.


Have fun with bttv,

  Gerd

--
Gerd Knorr <kraxel@goldbach.in-berlin.de>
