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@@ -1,33 +1,37 @@
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- Linux Braille Console
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+Linux Braille Console
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+=====================
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To get early boot messages on a braille device (before userspace screen
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readers can start), you first need to compile the support for the usual serial
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-console (see serial-console.txt), and for braille device (in Device Drivers -
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-Accessibility).
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+console (see :ref:`Documentation/serial-console.txt <serial_console>`), and
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+for braille device
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+(in :menuselection:`Device Drivers --> Accessibility support --> Console on braille device`).
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-Then you need to specify a console=brl, option on the kernel command line, the
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-format is:
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+Then you need to specify a ``console=brl``, option on the kernel command line, the
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+format is::
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console=brl,serial_options...
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-where serial_options... are the same as described in serial-console.txt
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+where ``serial_options...`` are the same as described in
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+:ref:`Documentation/serial-console.txt <serial_console>`.
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-So for instance you can use console=brl,ttyS0 if the braille device is connected
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-to the first serial port, and console=brl,ttyS0,115200 to override the baud rate
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-to 115200, etc.
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+So for instance you can use ``console=brl,ttyS0`` if the braille device is connected to the first serial port, and ``console=brl,ttyS0,115200`` to
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+override the baud rate to 115200, etc.
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By default, the braille device will just show the last kernel message (console
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mode). To review previous messages, press the Insert key to switch to the VT
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review mode. In review mode, the arrow keys permit to browse in the VT content,
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-page up/down keys go at the top/bottom of the screen, and the home key goes back
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+:kbd:`PAGE-UP`/:kbd:`PAGE-DOWN` keys go at the top/bottom of the screen, and
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+the :kbd:`HOME` key goes back
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to the cursor, hence providing very basic screen reviewing facility.
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-Sound feedback can be obtained by adding the braille_console.sound=1 kernel
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+Sound feedback can be obtained by adding the ``braille_console.sound=1`` kernel
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parameter.
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For simplicity, only one braille console can be enabled, other uses of
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-console=brl,... will be discarded. Also note that it does not interfere with
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-the console selection mechanism described in serial-console.txt
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+``console=brl,...`` will be discarded. Also note that it does not interfere with
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+the console selection mechanism described in
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+:ref:`Documentation/serial-console.txt <serial_console>`.
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For now, only the VisioBraille device is supported.
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