|  | // Copyright 2020-2022 F4PGA 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 | 
|  | // | 
|  | //     http://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 | 
|  |  | 
|  | module my_dff ( | 
|  | input d, | 
|  | clk, | 
|  | output reg q | 
|  | ); | 
|  | always @(posedge clk) q <= d; | 
|  | endmodule | 
|  |  | 
|  | module my_top ( | 
|  | inout  wire pad, | 
|  | input  wire i, | 
|  | input  wire t, | 
|  | output wire o, | 
|  | input  wire clk | 
|  | ); | 
|  |  | 
|  | wire i_r; | 
|  | wire t_r; | 
|  | wire o_r; | 
|  |  | 
|  | // IOB | 
|  | assign pad = (t_r) ? i_r : 1'bz; | 
|  | assign o_r = pad; | 
|  |  | 
|  | // DFFs | 
|  | my_dff dff_i ( | 
|  | i, | 
|  | clk, | 
|  | i_r | 
|  | ); | 
|  | my_dff dff_t ( | 
|  | t, | 
|  | clk, | 
|  | t_r | 
|  | ); | 
|  | my_dff dff_o ( | 
|  | o_r, | 
|  | clk, | 
|  | o | 
|  | ); | 
|  |  | 
|  | endmodule |