| // 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 top ( | 
 |   input clk, | 
 |   output [3:0] led | 
 | ); | 
 |  | 
 |   wire bufg; | 
 |   BUF bufgctrl ( | 
 |       .I(clk), | 
 |       .O(bufg) | 
 |   ); | 
 |   reg [pkg::BITS + pkg::LOG2DELAY-1 : 0] counter = 0; | 
 |   always @(posedge bufg) begin | 
 |     counter <= counter + 1; | 
 |   end | 
 |   assign led[3:0] = counter >> pkg::LOG2DELAY; | 
 | endmodule |