PROCEDURE CBCTWO(VAR B: PACKED ARRAY [lo..hi: integer] OF BCD_Digit;
                   VAR Bin: Word
    );
   EXTERNAL;
{*USER*
 Pascal-3 procedure which converts an input string of BCD digits
to an unsigned binary word. Converted word must fit in a 16-bit
word, or a run-time error will be declared, and zero returned.
}