On the Subject of Braille

This doesn’t feel right.

Braille consists of raised dots arranged in a regular grid. Each letter has 2×3 locations, each of which can have a raised dot or not. The following table shows the encoding for Unified English Braille.

• Move your finger over the module to feel the Braille message. The message consists of 4 Braille letters with 6 locations. However, some of the raised dots may be extraneous and some may be missing.
• The locations are numbered in columns from top to bottom, then left to right.
• To find out which locations are wrong, first convert the letters in the serial number to their alphabetic positions (where A=1, …, Z=26).
• Start with the location numbered according to the first character of the serial number plus one.

• For each subsequent character in the serial number, move forward that many locations plus one.
• Wherever you land each time, change a raised dot to an absent one and vice versa.
• If you go past the end of the message, wrap around to the beginning. (At times you may find yourself inverting the same location multiple times.)
• Finally, decode the word, find it in the following table and press on the indicated Braille letter.
• When an incorrect letter is pressed, a strike occurs and a new word is generated.