Procedure cpitas(pkt_id: message_packet_id_type;
                 var str: packed array [low..high:integer] of char);
   EXTERNAL;
{ Convert the Message Packet ID in PKT_ID to an alpha name.  STR
  can be a type0 or type1 string of any length.  The name will be
  truncated if required.  A maximum of 20 characters will be used
  in the string. }