| // Copyright (C) 2020-2021  The SymbiFlow Authors. | 
 | // | 
 | // Use of this source code is governed by a ISC-style | 
 | // license that can be found in the LICENSE file or at | 
 | // https://opensource.org/licenses/ISC | 
 | // | 
 | // SPDX-License-Identifier:ISC | 
 |  | 
 | module top ( | 
 |     input clk, | 
 |     input clk2, | 
 |     input [1:0] in, | 
 |     output [5:0] out | 
 | ); | 
 |  | 
 |   reg [1:0] cnt = 0; | 
 |   reg [1:0] cnt2 = 0; | 
 |   wire clk_int_1, clk_int_2; | 
 |   IBUF ibuf_inst ( | 
 |       .I(clk), | 
 |       .O(ibuf_out) | 
 |   ); | 
 |   assign clk_int_1 = ibuf_out; | 
 |   assign clk_int_2 = clk_int_1; | 
 |  | 
 |   PLLE2_ADV #( | 
 |       .CLKFBOUT_MULT(4'd12), | 
 |       .CLKIN1_PERIOD(10.0), | 
 |       .CLKOUT0_DIVIDE(4'd12), | 
 |       .CLKOUT0_PHASE(90.0), | 
 |       .DIVCLK_DIVIDE(1'd1), | 
 |       .REF_JITTER1(0.01), | 
 |       .STARTUP_WAIT("FALSE") | 
 |   ) PLLE2_ADV ( | 
 |       .CLKFBIN(builder_pll_fb), | 
 |       .CLKIN1(clk), | 
 |       .RST(cpu_reset), | 
 |       .CLKFBOUT(builder_pll_fb), | 
 |       .CLKOUT0(main_clkout0), | 
 |   ); | 
 |  | 
 |   always @(posedge clk_int_2) begin | 
 |     cnt <= cnt + 1; | 
 |   end | 
 |  | 
 |   always @(posedge main_clkout0) begin | 
 |     cnt2 <= cnt2 + 1; | 
 |   end | 
 |  | 
 |   middle middle_inst_1 ( | 
 |       .clk(ibuf_out), | 
 |       .out(out[2]) | 
 |   ); | 
 |   middle middle_inst_2 ( | 
 |       .clk(clk_int_1), | 
 |       .out(out[3]) | 
 |   ); | 
 |   middle middle_inst_3 ( | 
 |       .clk(clk_int_2), | 
 |       .out(out[4]) | 
 |   ); | 
 |   middle middle_inst_4 ( | 
 |       .clk(clk2), | 
 |       .out(out[5]) | 
 |   ); | 
 |  | 
 |   assign out[2:0] = {cnt2[0], cnt[0], in[0]}; | 
 | endmodule | 
 |  | 
 | module middle ( | 
 |     input  clk, | 
 |     output out | 
 | ); | 
 |  | 
 |   reg [1:0] cnt = 0; | 
 |   wire clk_int; | 
 |   assign clk_int = clk; | 
 |   always @(posedge clk_int) begin | 
 |     cnt <= cnt + 1; | 
 |   end | 
 |  | 
 |   assign out = cnt[0]; | 
 | endmodule |