yosys/tests/techmap/dfflibmap.lib

library(test) {
  /* D-type flip-flop with asynchronous reset and preset */
  cell (dffn) {
    area : 6;
    ff("IQ", "IQN") {
      next_state : "D";
      clocked_on : "!CLK";
    }
    pin(D) {
      direction : input;
    }
    pin(CLK) {
      direction : input;
    }
    pin(Q) {
      direction: output;
      function : "IQ";
    }
    pin(QN) {
      direction: output;
      function : "IQN";
    }
  }
  cell (dffsr) {
    area : 6;
    ff("IQ", "IQN") {
      next_state : "D";
      clocked_on : "CLK";
      clear      : "CLEAR";
      preset     : "PRESET";
      clear_preset_var1 : L;
      clear_preset_var2 : L;
    }
    pin(D) {
      direction : input;
    }
    pin(CLK) {
      direction : input;
    }
    pin(CLEAR) {
      direction : input;
    }
    pin(PRESET) {
      direction : input;
    }
    pin(Q) {
      direction: output;
      function : "IQ";
    }
    pin(QN) {
      direction: output;
      function : "IQN";
    }
  }
  cell (dffe) {
    area : 6;
    ff("IQ", "IQN") {
      next_state : "(D EN) | (IQ !EN)";
      clocked_on : "!CLK";
    }
    pin(D) {
      direction : input;
    }
    pin(EN) {
      direction : input;
    }
    pin(CLK) {
      direction : input;
    }
    pin(Q) {
      direction: output;
      function : "IQ";
    }
    pin(QN) {
      direction: output;
      function : "IQN";
    }
  }
}