Some users may need specific support because of e.g. some visual impairment. USB braille displays are detected automatically, but most other accessibility features have to be enabled manually. Some boot parameters can be appended to enable accessibility features. Note that on most architectures the boot loader interprets your keyboard as a QWERTY keyboard.
USB braille displays should be automatically detected. A textual version
of the installer will then be automatically selected, and support for the
braille display will be automatically installed on the target system.
You can thus just press Enter at the boot menu.
brltty is started, you can choose a braille
table by entering the preference menu.
Serial braille displays cannot safely be automatically detected
(since that may damage some of them). You thus need to append the
boot parameter to tell
brltty which driver it
driver should be replaced by the
two-letter driver code for your terminal (see the
driver code list).
port should be replaced by the name of the
serial port the display is connected to,
table is the name of the braille
table to be used (see the table code
list); the English table is the default. Note that the table can
be changed later by entering the preference menu.
Some accessibility devices are actual boards that are plugged inside the
machine and that read text directly from the video memory. To get them
to work framebuffer support must be disabled by using the
fb=false boot parameter. This will however reduce
the number of available languages.