cells/fa/sky130_fd_sc_ms__fa.functional.v

/*
 * Copyright 2020 The SkyWater PDK Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * SPDX-License-Identifier: Apache-2.0
*/


`ifndef SKY130_FD_SC_MS__FA_FUNCTIONAL_V
`define SKY130_FD_SC_MS__FA_FUNCTIONAL_V

/**
 * fa: Full adder.
 *
 * Verilog simulation functional model.
 */

`timescale 1ns / 1ps
`default_nettype none

`celldefine
module sky130_fd_sc_ms__fa (
    COUT,
    SUM ,
    A   ,
    B   ,
    CIN
);

    // Module ports
    output COUT;
    output SUM ;
    input  A   ;
    input  B   ;
    input  CIN ;

    // Local signals
    wire or0_out     ;
    wire and0_out    ;
    wire and1_out    ;
    wire and2_out    ;
    wire nor0_out    ;
    wire nor1_out    ;
    wire or1_out_COUT;
    wire or2_out_SUM ;

    //  Name  Output        Other arguments
    or  or0  (or0_out     , CIN, B            );
    and and0 (and0_out    , or0_out, A        );
    and and1 (and1_out    , B, CIN            );
    or  or1  (or1_out_COUT, and1_out, and0_out);
    buf buf0 (COUT        , or1_out_COUT      );
    and and2 (and2_out    , CIN, A, B         );
    nor nor0 (nor0_out    , A, or0_out        );
    nor nor1 (nor1_out    , nor0_out, COUT    );
    or  or2  (or2_out_SUM , nor1_out, and2_out);
    buf buf1 (SUM         , or2_out_SUM       );

endmodule
`endcelldefine

`default_nettype wire
`endif  // SKY130_FD_SC_MS__FA_FUNCTIONAL_V