Project-Oberon-BlackBox/BlackBox/Po/Files/Multiplier.Lola.txt

MODULE Multiplier (     (*NW 13.9.2014*)
  IN clk, run, u: BIT;
  OUT stall: BIT;
  IN x, y: WORD;   (*32 bit*)
  OUT z: [64] BIT);

  REG (clk) S: [6] BIT;   (*state*)
    P: [64] BIT;   (*product*)
  VAR w0: WORD;
    w1: [33] BIT;

BEGIN stall := run & (S # 33);
  w0 := P.0 -> y : 0;
  w1 := (S =32) & u -> {P.63, P[63:32]} - {w0.31, w0} : {P.63, P[63:32]} + {w0.31, w0};
  S := run -> S+1 : 0;
  P := (S = 0) -> {0'32, x} : {w1[32:0], P[31:1]};
  z := P
END Multiplier.