I am guessing you are at the part with the ruby. In the room above, there are several panels. They list the alphabet.
Translate it in your language. or you could get the guide book
There is no "braille decoder", you have to manually decode it yourself.
You go on the computer and search the word braille.
You have to use braille. if you look the word braille up in an encyclopedia,there should be a braille alphabet for you to use.
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You can research "How to read Braille" for more information.
On island one, there is a cave with a ruby and a full set of braille alphabet.
u don't get the braille to English translator in the game, but u can search it on the internet
There is no chart in the game but you can go to a sites that have video game information. Please see the below related link for a Braille Guide.
i suggest you buyt the fire red & leaf green guide book from BARNES & NOBLES to help you with the game...veronica
Braille key. With each Pokemon Ruby, Sapphire, Emerald, FireRed and LeafGreen version, you should obtain a Braille Key in the box. This gives you the symbols and the letters they stand for - which are used in the game. If you do not have this, it is easy to find. Wikipedia gives a Braille key under the heading "Writting Braille". Pokemon only uses the alphabetic letters and the symbols for the full stop and the comma. http://en.wikipedia.org/wiki/Braille
It's on Six Island in that cave with the Braille.