ENTITY sff1_x4 IS
GENERIC (
  CONSTANT area          : NATURAL := 4500;
  CONSTANT cin_ck        : NATURAL := 8;
  CONSTANT cin_i         : NATURAL := 8;
  CONSTANT rdown_ck_q    : NATURAL := 800;
  CONSTANT rup_ck_q      : NATURAL := 890;
  CONSTANT taf_ck_q      : NATURAL := 500;
  CONSTANT tar_ck_q      : NATURAL := 500;
  CONSTANT thf_i_ck      : NATURAL := 0;
  CONSTANT thr_i_ck      : NATURAL := 0;
  CONSTANT tsf_i_ck      : NATURAL := 585;
  CONSTANT tsr_i_ck      : NATURAL := 476;
  CONSTANT transistors   : NATURAL := 26
);
PORT (
  ck     : IN  BIT;
  i      : IN  BIT;
  q      : OUT BIT;
  vdd    : IN  BIT;
  vss    : IN  BIT
);
END sff1_x4;

ARCHITECTURE vbe OF sff1_x4 IS
  SIGNAL sff_m   : REG_BIT REGISTER;

BEGIN
  ASSERT (vdd AND NOT (vss))
  REPORT "power supply is missing on sff1_x4"
  SEVERITY WARNING;

  label0 : BLOCK ((ck AND NOT (ck'STABLE)) = '1')
  BEGIN
    sff_m <= GUARDED i;
  END BLOCK label0;

  q <= sff_m after 1700 ps;
END;