ENTITY rom_dec_colbuf IS
PORT (
  a      : in  BIT;
  ax     : out BIT;
  nax    : inout BIT;
  vdd	  : in  BIT;
  vss	  : in  BIT
);
END rom_dec_colbuf;

ARCHITECTURE VBE OF rom_dec_colbuf IS

BEGIN
  ASSERT (vdd and not (vss))
  REPORT "power supply is missing on rom_dec_colbuf"
  SEVERITY WARNING;

  nax <= not a;
  ax  <= not nax;
END;