Typing Ascii Character

[Art]

   I'd like some advice on putting a function call for an ASCII character in
my keyboard file.
   I'd like to put a hard hyphen in my keyboard file (under the hyphen key),
so I just press the key involved, and the hard hyphen appears. It's ASCII 45.
   An equivalent XyWrite program that successfully does this is: R4 R5. But
despite several experiments, I can't figure out the keyboard-file version of
this program (R45? R4 R5?? etc. etc.); I'm probably missing something obvious,
though I have other function calls in my keyboard file. (Just putting the hard
hyphen by itself in the keyboard file doesn't seem to work, by the way. It ends
up being a plain ordinary hyphen.)
   Thanks for any suggestions.