Also check out the Chr$(letter) and Asc(letter$) commands, so you can replace that very long function "Convert_to_string$".
Chr$() accepts a ASCII value and converts it to a character (like your function), while Asc() accepts a character and converts it back to a ASCII value.
Chr$() accepts a ASCII value and converts it to a character (like your function), while Asc() accepts a character and converts it back to a ASCII value.