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