Expanding on a previous tip. Here are some methods for figuring out the value of a given character.
1) Using gf - place the character under a character and hit ga in normal mode to obtain it's ascii value.
2) Using g8 - same as above but applies to UTF-8 characters.
3) :set list - toggles displaying unprintable characters.
4) pipe into the shell command od -c
5) type the :ascii ex command to display a characters ascii value
6) use cat -vET filename