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diff --git a/Documentation/DocBook/media/v4l/dev-teletext.xml b/Documentation/DocBook/media/v4l/dev-teletext.xml deleted file mode 100644 index bd21c64d70f3..000000000000 --- a/Documentation/DocBook/media/v4l/dev-teletext.xml +++ /dev/null @@ -1,29 +0,0 @@ - <title>Teletext Interface</title> - - <para>This interface was aimed 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 could be found on old -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 was defined in -the kernel header file <filename>linux/videotext.h</filename>, the -specification is available from <ulink url="ftp://ftp.gwdg.de/pub/linux/misc/videotext/"> -ftp://ftp.gwdg.de/pub/linux/misc/videotext/</ulink>. (Videotext is the name of -the German public television Teletext service.)</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.</para> - - <para>However, teletext decoders were quickly replaced by more -generic VBI demodulators and those dedicated teletext decoders no longer exist. -For many years the vtx devices were still around, even though nobody used -them. So the decision was made to finally remove support for the Teletext API in -kernel 2.6.37.</para> - - <para>Modern devices all use the <link linkend="raw-vbi">raw</link> or -<link linkend="sliced">sliced</link> VBI API.</para> |