Subversion Repositories bluespec-h264

package mkSatCounter;

interface SatCounter#(numeric type bits);

  method Action up();

  method Action down();

  method Bit#(bits) value();

endinterface

module mkSatCounter#(Bit#(bits) init) (SatCounter#(bits));

  Reg#(Bit#(bits)) counter <- mkReg(init);

  RWire#(Bit#(0)) up_called <- mkRWire();

  RWire#(Bit#(0)) down_called <- mkRWire();

  rule update;

    if(up_called.wget matches tagged Valid .x)

      begin

        if(down_called.wget matches tagged Invalid)

          if(counter != ~0)

            counter <= counter + 1;

      end

    else

        if(down_called.wget matches tagged Valid .x)

            if(counter != 0)

               counter <= counter - 1;

  endrule

  method Action up();

    up_called.wset(0);

  endmethod

  method Action down();

    down_called.wset(0);

  endmethod

  method Bit#(bits) value();

    return counter;

  endmethod

endmodule

endpackage