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author | Mauro Carvalho Chehab <mchehab@redhat.com> | 2009-09-13 22:16:04 -0300 |
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committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2009-09-18 23:47:55 -0300 |
commit | 8e080c2e6cadada82a6b520e0c23a1cb974822d5 (patch) | |
tree | 991450ff1abba98e5313906478c33816a202ccab /Documentation/DocBook/v4l/dev-teletext.xml | |
parent | f4e96deb4513d044653027d4921fd7592195503a (diff) | |
download | op-kernel-dev-8e080c2e6cadada82a6b520e0c23a1cb974822d5.zip op-kernel-dev-8e080c2e6cadada82a6b520e0c23a1cb974822d5.tar.gz |
V4L/DVB (12761): DocBook: add media API specs
The V4L and DVB API's are there for a long time. however, up to now,
no efforts were done to merge them to kernel DocBook.
This patch adds the current versions of the specs as an unique compendium.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'Documentation/DocBook/v4l/dev-teletext.xml')
-rw-r--r-- | Documentation/DocBook/v4l/dev-teletext.xml | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/Documentation/DocBook/v4l/dev-teletext.xml b/Documentation/DocBook/v4l/dev-teletext.xml new file mode 100644 index 0000000..59f9993 --- /dev/null +++ b/Documentation/DocBook/v4l/dev-teletext.xml @@ -0,0 +1,40 @@ + <title>Teletext Interface</title> + + <para>This interface aims at devices receiving and demodulating +Teletext data [<xref linkend="ets300706" />, <xref linkend="itu653" />], evaluating the +Teletext packages and storing formatted pages in cache memory. Such +devices are usually implemented as microcontrollers with serial +interface (I<superscript>2</superscript>C) and can be found on older +TV cards, dedicated Teletext decoding cards and home-brew devices +connected to the PC parallel port.</para> + + <para>The Teletext API was designed by Martin Buck. It is defined in +the kernel header file <filename>linux/videotext.h</filename>, the +specification is available from <ulink url="http://home.pages.de/~videotext/"> +http://home.pages.de/~videotext/</ulink>. (Videotext is the name of +the German public television Teletext service.) Conventional character +device file names are <filename>/dev/vtx</filename> and +<filename>/dev/vttuner</filename>, with device number 83, 0 and 83, 16 +respectively. A similar interface exists for the Philips SAA5249 +Teletext decoder [specification?] with character device file names +<filename>/dev/tlkN</filename>, device number 102, N.</para> + + <para>Eventually the Teletext API was integrated into the V4L API +with character device file names <filename>/dev/vtx0</filename> to +<filename>/dev/vtx31</filename>, device major number 81, minor numbers +192 to 223. For reference the V4L Teletext API specification is +reproduced here in full: "Teletext interfaces talk the existing VTX +API." Teletext devices with major number 83 and 102 will be removed in +Linux 2.6.</para> + + <para>There are no plans to replace the Teletext API or to integrate +it into V4L2. Please write to the linux-media mailing list: &v4l-ml; +when the need arises.</para> + + <!-- +Local Variables: +mode: sgml +sgml-parent-document: "v4l2.sgml" +indent-tabs-mode: nil +End: + --> |