VMS Help PASCAL, Predeclared Routines, Transfer, CHR  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  The CHR function returns a char value whose ordinal value in the
  ASCII  character set is the parameter, provided such a character
  exists.

  Syntax:

     CHR( x )

  The parameter 'x' must be integer or unsigned and have  a  value
  from 0 to 255.